Meperidine

What Kind of Drug Is It?

Meperidine (meh-PER-ih-deen) is best known by its brand name, Demerol. It is a synthetic opioid, meaning that it is a drug created by chemists to imitate certain medicinal qualities of opium, a drug made from flowers called opium poppies. Opioids are narcotic drugs that cause drowsiness and mood changes by interacting with the nerve cells in a person's brain. They can cause physical addiction with extended use. Physical addiction occurs when the body becomes dependent on a particular chemical substance or a combination of chemicals.

Opioids are controlled substances. This means they are available only with a doctor's prescription. Meperidine is a narcotic analgesic, or pain reliever. It is most commonly used in hospitals for patients who have just had surgery.

An analgesic is any chemical substance that has the ability to control or relieve pain. Many familiar analgesics, including acetaminophen (Tylenol), aspirin, and ibuprofen (Advil; Motrin), are sold in drugstores without a doctor's prescription. These over-the-counter (OTC) drugs must be taken with care to avoid unpleasant or dangerous side effects, but they do not have the power to create physical or psychological addiction.

By contrast, meperidine and other narcotic analgesics are highly addictive substances. They are legal but controlled substances. The only people who are supposed to have access to them are those whose doctors have prescribed the medications to treat specific medical conditions. Some other well-known prescription analgesics include hydrocodone (brand name, Vicodin) and oxycodone (brand names, OxyContin, Percocet, and Percodan). (An entry on oxycodone is also available in this encyclopedia.)

Official Drug Name: Meperidine (meh-PER-ih-deen), meperidine hydrochloride, Demerol, Pethidine (PETH-ih-deen)

Also Known As: Demmies

Drug Classifications: Schedule II, synthetic opioid

As of 2005, drug treatment counselors and law enforcement officials were alarmed at the increasing use of prescription-only opioids such as hydrocodone, meperidine, and oxycodone for illegal, nonmedical purposes. Among those most likely to abuse drugs like OxyContin, Demerol, and Vicodin are teens and young adults who engage in recreational drug use, to experience the mood-altering effects of the drugs. Other abusers of prescription drugs include individuals who have become physically addicted to an opioid after using it to treat a legitimate medical condition.

Overview

Narcotic analgesics are prescribed by doctors to treat moderate to severe pain. The first narcotics were opiates, which are any drugs derived from the opium poppy or synthetically produced to mimic the effects of the opium poppy. Opiates tend to decrease restlessness, bring on sleep, and relieve pain. Opium is a plant-based, chemically complex drug that has been used for thousands of years as medicine and as a recreational drug. Although it does block pain, it is highly addictive. The intensity of its effects is difficult to regulate from one use to the next, which makes it impractical as a pharmaceutical drug.

Prescription Drug Abuse by Teens

The abuse of prescription drugs by teens has increased dramatically in the twenty-first century. Did you know that:

• Nearly one out of five teenagers has taken Vicodin to get high.
• In 2004, teens were more likely to use a prescription drug than a so-called "street" drug to get high.
• Some middle and high school students falsely believe that prescription painkillers are safe to use as recreational drugs.
• These same students also believe that using prescription drugs to get high is not illegal.
• Some students misuse prescription drugs in an attempt to enhance their athletic performance.
• Hundreds of Internet sites offer prescription drugs to anyone with a credit card; 90 percent do not always verify the age of the buyer.
• Prescription drug sales have climbed 400 percent since 1990, in part due to "doctor shopping."
• "Doctor shopping" is the practice of finding a doctor who will write illegal prescriptions, or of getting prescriptions for a particular drug from more than one doctor at a time.

One of the chemical components of opium is morphine, an addictive opiate that is used to kill pain and bring on relaxation and sleep. In 1806, German chemist Friedrich Sertürner (1783–1841) was finally able to isolate pure morphine from opium. This resulted in the first pure, highly effective analgesic (painkilling) drug for medical use. In 1832, codeine, the other major chemical in opium, was isolated and used as medicine. Both drugs are still in use, individually and in combination with other drugs, because they are very effective pain relievers. However, both are also highly addictive. That is why researchers have continued to try to develop better opiate-like drugs—that is, drugs that possess the pain-relieving power of morphine and codeine, but with fewer negative effects.

One of the first wholly synthesized opioids—or opiate-like drugs—was meperidine. It was first created in the 1930s. It was produced from human-made chemicals, rather than from any part of the opium poppy. Meperidine is still in medical use today.

More About Opioids

Semi-synthetic opioids are drugs that are synthesized with one of the natural opiates, morphine or codeine. Examples of these are hydrocodone (Vicodin) and oxycodone (OxyContin). Both the synthesized and semi-synthesized opioids are drugs specifically created to produce effects similar to opium. They each have particular benefits and drawbacks. Morphine and codeine are still used, however, because researchers still have not found anything that works quite as well as the natural opiates themselves. In addition to their pain-relieving characteristics, opiates and opioids also have something else in common: They are all physically and psychologically addictive to one degree or another. Scientists are still working to try to find a chemical compound that will function as effectively as an opiate-like substance without the dangers of addiction.

What Is It Made Of?

Meperidine hydrochloride (the drug's full name) is a synthetic opioid. It is created through the reaction of two chemicals: dichlorodiethyl methylamine (pronounced di-KLO-ro-di-eh-thyl meh-thyl-A-mine) and benzyl cyanide, an oily, colorless liquid. The chemical name for the resulting white crystalline substance is ethyl 1-methyl-4-phenyl-isonipecotate hydrochloride.

Meperidine is synthesized exclusively from laboratory-made chemicals, and not from any part of the opium poppy. That is why it is called a totally synthetic opioid. By contrast, other well-known narcotics that imitate the effects of opium are said to be semi-synthetic opioids. These drugs are produced with one of the naturally occurring opiates as a starting material. Natural opiates include codeine and morphine. A chemical modification of codeine, another opiate, results in hydrocodone, a highly addictive but effective painkilling drug. By contrast, a chemical alteration of morphine results in heroin, a dangerous and highly addictive narcotic that has no legal use and none of the benefits of narcotic medications.

How Is It Taken?

Meperidine is taken orally or injected. The oral forms of the drug include tablets and syrup. Tablet sizes range from 25 milligrams to 100 milligrams per tablet. The syrup form contains 50 milligrams of meperidine per 5 milliliters of liquid. A typical oral dosage of meperidine is 50 milligrams to 150 milligrams every three to four hours.

The body responds to meperidine more quickly when it is injected, so those dosages are usually about half that of the oral forms of the drug. Injections may be given in the muscle, under the skin, or directly into the bloodstream. Doses are usually given every three to four hours, although an intravenous (IV) administration of meperidine is often maintained at a low, continual therapeutic dose.

Hospitalized patients receiving meperidine for pain control after surgery sometimes use a system called patient controlled anesthesia (PCA). A PCA machine allows a specific amount of meperidine to be administered intravenously each hour. However, the patient has control over when the medicine is dispensed. This reduces the need for a nurse to give the patient an injection every three to four hours, and it keeps the drug at a more constant level in the body for better pain relief. The PCA machine is programmed so that it cannot give the patient too much of the drug. This prevents the potential for an overdose.

Meperidine is abused by people used to taking nonprescription street drugs. Sometimes they crush the meperidine tablets and then chew, snort, or dissolve the drug in a liquid and inject it. Misusing meperidine can dangerously affect the way the body processes the drug.

Are There Any Medical Reasons for Taking This Substance?

Demerol, the brand name for meperidine, is one of the most commonly used narcotic analgesics in U.S. hospitals. It is used to treat moderate to severe pain, especially immediately after surgery. It is sometimes used together with anesthesia before and during operations. Meperidine is also frequently given to pregnant women during labor and delivery. It is not recommended for treating pain in infants and small children or the elderly.

For several reasons, meperidine is used in hospitals more than it is prescribed for at-home use. First, it is more effective in treating the acute (immediate, short-term) pain that follows surgery than the chronic (longer-lasting, ongoing) pain that a patient might experience during recovery at home. It is also eliminated from the body quicker than other opioids, which means that it must be taken more often than other narcotic drugs in order to maintain pain relief. This rapid elimination of the drug also means that its pain-relieving effects are not as consistent as those of other opioids.

Usage Trends

Meperidine is a prescription drug with both legal and illegal usage trends. Meperidine was, and is, particularly useful for the treatment of acute pain, but it is not as effective in controlling chronic pain. Newer synthetic and semi-synthetic opioids include chemical compounds that relieve pain for longer periods of time, but many of the side effects are similar.

Designer Meperidine

In the early 1980s, a new drug was created that imitated the chemistry and effects of meperidine. This so-called "designer" meperidine was known as MPPP. It was manufactured in illegal drug labs where mistakes and unreliable conditions sometimes led to unintended results. One such consequence was the contamination of MPPP with a poisonous chemical by-product called MPTP. This is a toxin that can destroy nerve cells in certain parts of the brain.

When people ingested the MPPP that had been tainted with MPTP, they suffered neurological symptoms that mimicked Parkinson's disease. Their muscles became rigid and they exhibited uncontrollable twitching. The damage was permanent.

The dangerous "designer" meperidine was one of many drugs called "analogs," which means they were created specifically to be similar to, but not exactly like, other drugs. Why was this done? Because illegal drug labs could sometimes avoid Drug Enforcement Administration (DEA) consequences by making drugs whose specific chemical formulas were not listed on the Schedule of Controlled Substances. Illegal drug manufacturers could get away with making a drug that acted like a highly controlled substance, but had a slightly different chemical structure than the regulated drug. For a time this was not illegal.

In 1986, however, legislation was passed to stop this practice and make the manufacture of analog drugs illegal. It was finally against the law to create a drug that was designed to produce effects similar to any drug already listed as a controlled substance.

Although meperidine is still used in hospitals and emergency treatment settings, Drug Enforcement Administration (DEA) figures show that between 1990 and 1996, the legitimate medical use of meperidine in the United States decreased by 35 percent. Worldwide, the legitimate use of meperidine dropped 20 percent between the early 1980s and 1999. The decline in usage of meperidine is related to the development of newer opioids that are safer and longer lasting than meperidine.

Street usage of meperidine became a law enforcement issue during the 1980s, when it was frequently used as a substitute for heroin. In particular, two meperidine analogs, or imitation drugs, became popular: MPPP and PEPAP. Heroin users like MPPP because it produces a heroin-like euphoria when it is injected. The creation of these analogs is now completely illegal. This occurred, in part, because during the 1980s street drug labs produced an analog that contained MPTP, a poison that caused serious and irreversible neurological damage in users.

Among opioids, Demerol (brand name of meperidine) is not as frequently prescribed outside hospital settings as Vicodin and OxyContin, so its abuse is not as widespread or well-publicized as the abuse of these other drugs. Demerol is more readily available to medical professionals—doctors, nurses, pharmacists or others who work in a hospital or emergency care clinic—than to others. It is sometimes stolen from ambulances or standalone emergency care facilities through street robberies or "inside" thefts perpetrated by employees.

Prescription Drug Abuse Grows

The illegal use of prescription drugs, including opioids like meperidine, is a large and growing segment of the complete drug abuse picture. Several nationwide studies track the use of both legal substances (prescription medications and over-the-counter, or OTC, drugs) and illegal drugs such as marijuana and cocaine. The National Household Survey on Drug Abuse (NHSDA), which is conducted by the U.S. Department of Health and Human Services, collects yearly statistical data on five drug groups. These include: 1) marijuana and hashish; 2) psychotherapeutic drugs, which are generally prescription drugs that can be used illegally to get high; 3) cocaine and crack; 4) hallucinogens, which are substances that bring on hallucinations, which alter the user's perception of reality; and 5) inhalants. Psychotherapeutic drugs include stimulants, sedatives, tranquilizers, and pain relievers. Meperidine and other opioids make up the majority of the pain relievers in that group.

In 2003, the NHSDA found that 4 percent of all people between twelve and seventeen reported that they had used some kind of psychotherapeutic medication during the previous month for a nonmedical—illegal—purpose. More than 9.2 percent in that age group reported such use at any time during the year. In 2003, 6 percent of individuals between eighteen and twenty-five reported nonmedical use of prescription drugs in the month prior to the date on which they were surveyed. That was up from 3.6 percent in 2000 and just 1.6 percent in 1994.

According to the NHSDA's 2000 study, approximately 1.6 million Americans used prescription pain relievers nonmedically for the first time in 1998. During the 1980s, there were generally fewer than 500,000 first-time users per year. The trend shows steadily rising numbers of people using prescription drugs for nonmedical use.

New Generation of Abusers

Another yearly study is conducted by the Partnership for a Drug-Free America. In April 2005, the Partnership released the results of its seventeenth annual national study of teen drug abuse. The 2004 Partnership Attitude Tracking Study (PATS) reported that one of every five teenagers has used a prescription painkiller as a recreational drug. The most frequently abused brand-name opioids were Vicodin (reported by 18 percent of respondents) and OxyContin (reported by 10 percent of respondents). These are narcotic analgesics whose nonmedical effects on users are similar to those of meperidine (brand name Demerol). Overall, teen misuse and abuse of prescription drugs, including opioids, is growing rapidly. As a result, teens were given the nickname "Generation Rx." (See chart on this page.)

Teens are drawn to the use of prescription drugs for a variety of reasons, including ease of availability, relatively low cost, and a perception that the pills are harmless because they are legal. According to Carol Falkowski, a drug researcher at Hazelden, a well-known substance abuse treatment center in Minnesota, young drug users often prefer prescription drugs because they believe they are "cleaner, safer and less illegal." Teens also admit that they find prescription drugs more attractive than other substances because they are not as likely to leave signs of use, such as the visible disorientation of being drunk or the odor that results from smoking marijuana.

Generation Rx

"Rx" is a traditional abbreviation for the word "prescription." "Generation Rx" is a term coined in 2005 to reflect the soaring popularity of prescription drugs among teens. This nonmedical, and illegal, use of drugs such as Ritalin, Vicodin, OxyContin, Xanax, and Valium is sometimes called "pharming" by drug counselors and by teens themselves.

The phenomenon is not limited to teens, however. Well-known public figures including actors Matthew Perry and Melanie Griffith and athletes Brett Favre and Darryl Strawberry have publicly battled addictions to the prescription painkiller Vicodin. In October 2003, radio personality and former ESPN sports analyst Rush Limbaugh entered a treatment center to deal with his addiction to OxyContin.

While adults often become addicted to pain pills after using them for a legitimate medical reason, teen use of the drugs is typically more recreational. If there is no legitimate medical need to get a prescription from the family doctor, some teens resort to stealing pills from medicine cabinets at home or order them from Internet pharmacy sites.

Teens mistakenly believe that because these are brand-name drugs, manufactured by legal pharmaceutical companies, they are safe. Teens often do not realize how dangerous it is to mix prescription drugs with alcohol, or to combine different drugs "to see what happens." Even adults frequently are not aware that large quantities of the over-the-counter medicine acetaminophen—commonly known as Tylenol—can cause liver damage. This is important to know because one of the main ingredients in Vicodin is acetaminophen.

Students often do not realize, either, that the nonmedical use of prescription medicines is against the law. "Generation Rx" teens who commit crimes related to the abuse of prescription drugs not only risk addiction or other physical consequences, they also face job loss, jail time, or being denied access to scholarships and other financial aid to further their post-high school education.

Effects on the Body

Physical pain occurs when illness or injury causes pain signals to be transmitted to the brain through nerve cells in the body. The pain-relieving effect of an opioid like meperidine is produced when

the drug blocks these signals by interacting with proteins called opioid receptors that exist on the surface of nerve cells. The chemical relationship is something like keys and locks. The narcotic drug fits into the receptor proteins and opens a pathway for chemical changes that reduce the ability of the nerve cell to transmit pain signals. When this happens, fewer pain signals are received by the brain, which means that the person taking the drug feels less pain.

If opioids are used when one is not in pain, the chemical changes in the nerve cells and the brain can produce feelings of euphoria, or a state of extreme happiness and well-being. When this occurs over a period of time, the nerve cells become tolerant of the effect, which means that more of the chemical substance is needed to produce the same sensation. Over the course of time, the body also becomes addicted to the basic chemical action of the drug. Thus, if the drug is discontinued, the user experiences unpleasant physical symptoms of drug withdrawal.

Addiction Problems

Opioids can also cause psychological addiction or dependence. This is present when a person craves a drug and feels a compulsive need to take it, no matter what the consequences may be. This is what drives many people to commit crimes ranging from fraud to robbery in order to acquire the prescription drugs on which they are dependent. They become psychologically addicted to the emotional sensations that accompany the physical effects of the drug. Psychological addiction generally does not occur when people use prescription opioids for long-term, chronic pain. However, it is possible for legitimate use to turn into abuse in individuals who have developed physical dependence when their doctors decide that prescription narcotics are no longer appropriate as treatment. This is what has happened to many people who have become hooked on these painkilling drugs that were prescribed for them for long-term use after surgery or an injury of some kind.

Meperidine is generally used to treat acute pain, so medical use does not usually lead to either physical dependence or tolerance. Prescription users of meperidine do not need more and more of the drug to get the needed level of pain relief. However, when the drug is used specifically to get high, users typically develop both physical tolerance and addiction and psychological addiction. This means they not only crave the drug and physically need more of the drug just to get high, they also need to keep taking the drug to avoid the discomfort of chemical withdrawal.

When a person who is addicted to the physical aspects of a drug suddenly stops taking that drug, withdrawal symptoms occur. Opioid withdrawal is not life threatening, as is sometimes the case with the physical withdrawal from some heavily used substances, such as alcohol and barbiturates. It is unpleasant, however. Short-term withdrawal symptoms include anxiety, yawning, sweating, abdominal cramps and diarrhea, chills and "goose bumps," and a runny nose. Symptoms begin to appear about four or five hours after the last dose. They are at their most intense between thirty-six and seventy-two hours later, and are generally over within a week or ten days. Complete detoxification and recovery from physical addiction can take six months or more.

Side Effects of Meperidine Use

Even when meperidine and other opioids are taken under medical supervision, side effects can occur. Opioids relieve pain by temporarily altering the function of nerve cells. In addition to reducing one's pain, this may also cause mental confusion, drowsiness, dizziness and/or nausea, constipation, sweating, low blood pressure, or a slow heartbeat. More serious effects include convulsions and respiratory distress. These most frequently occur if the drug's dosage is too high, or if a patient combines meperidine with alcohol or other drugs.

Patients with kidney or liver disease may be at risk of nervous system damage if they use meperidine for a significant length of time. A by-product of meperidine called normeperidine is broken down in the liver and excreted by the kidneys. Someone with impaired function of either organ may develop high levels of normeperidine, which can be toxic (poisonous) to the nervous system.

People with a history of seizures, or those who have experienced recent head trauma, which puts them at risk of a first seizure, should avoid the use of meperidine. This is because meperidine presents a higher risk for seizures than other opioids. Other serious, but rare, neurological side effects include delirium, hallucinations, and tremors. Allergic reactions to meperidine are unusual, but severe cases can cause symptoms such as cold, clammy skin, generalized weakness, respiratory arrest, and unconsciousness or coma.

Reactions with Other Drugs or Substances

Because meperidine acts as a central nervous system depressant, no other similarly acting substance should be taken with meperidine, unless it is under the close supervision of a physician. Alcohol is a prime example of this. So are drugs known as sedatives, which are used to treat anxiety and calm people down. A large enough dose of any opioid, including meperidine, can stop a person's breathing completely, resulting in death. In combination with alcohol or sedatives, this reaction can occur at much lower doses.

Drugs to be avoided while taking meperidine include most antihistamines, sleeping pills, and any drugs that are in the same classification as Valium. Several types of antidepressants should be used with great caution or not at all in combination with meperidine. These include tricyclics (brand name examples include Elavil and Aventyl); SSRIs (selective serotonin reuptake inhibitors; some name brand examples include Prozac, Zoloft, and Paxil); and MAOIs (monoamine oxidase inhibitors; examples include Marplan and Nardil). Even moderate therapeutic doses of meperidine administered up to two weeks after a patient has used an MAOI-class drug can result in unpredictable and severe reactions, including coma and death.

Treatment for Habitual Users

Meperidine is a highly addictive, Schedule II opioid narcotic. A high potential for addiction usually means that long-term use is risky. Long-term use may be measured as years of continual use, or as a repeating cycle of periods of use interrupted by times when the drug is not being used. The longer a narcotic drug is used, the more likely it is that a person may need help to quit using it. People who become addicted to drugs like meperidine or other prescription painkillers are less likely than users of street drugs to seek assistance in withdrawing from taking the drug.

When an opioid is suddenly discontinued after a long period of use, serious and uncomfortable withdrawal symptoms generally occur. Most people who manage to overcome an addiction to meperidine do it on their own, but many cases require professional help. Symptoms of physical withdrawal from meperidine may include restlessness, pain in bones and muscles, insomnia, diarrhea, a runny nose, chills with goose bumps, and involuntary leg movements. Symptoms of psychological addiction include becoming severely depressed and having an almost uncontrollable craving or desire for the drug.

For a chronic addiction, meaning drug use and addiction that has lasted more than a year, methadone may be used in a medically supervised withdrawal process. (An entry on methadone is also available in this encyclopedia.) Methadone is another opioid. It is used in progressively smaller doses to help users break free of addictions to more powerful drugs. Methadone helps reduce withdrawal symptoms, including the craving of another opioid, and it has fewer side effects than other opioids.

An Alternative Treatment

Since 2002, drug treatment specialists have experimented with a new drug called buprenorphine (BYOO-preh-NOR-feen). One day it might replace the use of methadone to treat withdrawal symptoms. Early results are promising, but access to the drug is still strictly limited by government control.

Researchers are hopeful that buprenorphine can help people break free of addiction to opiates such as heroin and codeine, and to opioid pain pills like Demerol, Vicodin, and OxyContin. Also known by the names Suboxen and Subutex, the drug has similar effects on the body as methadone but it is not as addicting as other opiate or opioid-like drugs. Controlled doses of buprenorphine help people withdraw from their addiction to drugs like heroin and Vicodin without some of the complications of methadone treatment. Doctors who have used buprenorphine consider it a successful treatment option and they wish more patients could benefit from it.

According to federal law, only doctors who earn special certification from the Drug Enforcement Administration (DEA) are allowed to prescribe buprenorphine. In addition, the law specifies that each certified doctor or group practice is limited to treating thirty patients at a time with the drug. By early 2005, only 4,850 of 600,000 U.S. doctors—fewer than 1 percent—had earned certification to dispense the drug. Of those, only 1,500 had treated patients with it.

Cost of Abuse

At between $300 and $350 per month for treatment, buprenorphine is expensive, and many insurance companies will not pay for it. However, people with pain pill addictions often spend more than $300 every month to support their habits. Plus, the true cost of addiction can include the breakup of a marriage or family, the loss of a job, and a criminal record.

What is the best balance between controlling access to the drug and making it available to all who need it in a treatment setting? The DEA wants to maintain close restrictions on the use of buprenorphine to prevent a possible new drug abuse "epidemic." Doctors who use it to treat patients with opioid addictions want to be able to help more people, and sooner, rather than later. While the waiting lists grow, doctors and other addiction treatment professionals will have to work with federal lawmakers to figure out how to best use this resource.

Consequences

Meperidine and other opioids offer specific benefits when they are used appropriately. However, the benefits of the drugs must be weighed against the possibility of abuse or addiction. An established addiction is costly to maintain—financially, emotionally, and physically. Sufferers admit that a serious opioid addiction consumes all their energy. Everything in their lives eventually revolves around obtaining more of the drug. When the drug becomes the focus of life, they lose friends, alienate family members, and often find themselves unable to hold a job.

Those who are caught committing crimes to maintain their addiction may end up serving jail or prison time. The ultimate consequence may be the loss of life that can result from the abuse of a prescription drug—whether it is from the physical effects of an overdose or through violence that occurs as a result of the addiction.

When meperidine is used exclusively as a recreational drug, consequences include the very real possibility of overdose or severe interactions with other substances. According to the Partnership for a Drug-Free America, nearly half of all teens believe that the recreational use of prescription drugs is safer than the use of illicit street drugs. About one-third of teens do not realize that narcotic painkillers are addictive.

Unexpected Outcomes

Teens are drawn to the use of prescription drugs for a variety of reasons, including ease of availability, relatively low cost, and a perception that the pills are harmless because they are legally obtainable by prescription. This lack of knowledge about the physical effects of narcotics, as well as the consequences of using them illegally, can result in unexpected and tragic outcomes.

Healer or Dealer?

On April 14, 2005, Dr. William E. Hurwitz, a well-known pain doctor from McLean, Virginia, was sentenced to twenty-five years in prison. He was convicted in December 2004 of narcotics trafficking and running a drug conspiracy. The doctor was held responsible in the death of one patient and the serious injury of two others.

The case was watched closely because it reflected the ongoing debate over whether doctors should be allowed to prescribe large quantities of narcotic medications to patients who are in chronic pain. Critics of Dr. Hurwitz said that he continued providing patients with massive doses of highly addictive drugs, even when he knew that some of them were misusing or abusing their medications or selling them to others. The doctor's supporters said that he was a dedicated and caring medical professional. They believed he was determined to provide chronic pain sufferers with the relief they needed, despite intense government scrutiny of his drug prescription activity.

How the outcome of this case will affect the prescribing activity of doctors who specialize in pain control remains to be seen. However, the United States has an aging population that is living longer. With more people living more years with chronic conditions that cause pain, the "access vs. control" debate over pain relief drugs will continue.

The misuse of meperidine and other opioids affects people who live with chronic pain, because doctors become reluctant to write prescriptions that are needed for adequate pain relief. Members of the medical community agree that more education is needed by both doctors and patients to help prevent abuse and addiction. They want to ensure that patients truly in need are not denied access to meperidine and other narcotics based on misperceptions and fear. The benefits for individuals and society are great when pain is treated safely and effectively.

The Law

Meperidine is classified as a Schedule II controlled substance, which means that it is strictly regulated by both United States and international laws and agencies. In the United States, the Food and Drug Administration (FDA) and the Drug Enforcement Administration (DEA) control the manufacture and distribution of meperidine. International control is coordinated by the International Narcotic Control Board (INCB).

A Schedule II drug is available by prescription only. It is illegal to write a prescription or an order for meperidine without a valid medical license. Medical doctors, osteopathic doctors, podiatrists, dentists, and veterinarians are the only professionals allowed to legally prescribe meperidine and other Schedule II drugs. Medical professionals who intentionally write multiple prescriptions for patients without a valid medical reason may end up in prison. It is an even more serious crime to write and fill phony prescriptions for profit.

Doctor Shopping and Other Illegal Methods

It is illegal for individuals to obtain prescriptions for meperidine and other opioids by lying about their symptoms. Another dishonest way that people try to get drugs for illegal use is by going to several different doctors within the same time period and receiving prescriptions from each of them. Then they pay cash to buy each prescription at a different pharmacy to avoid being tracked by pharmacy or insurance records. This practice has been given the name "doctor shopping." As of 2004, at least nineteen states had laws against doctor shopping. Prescription Monitoring Programs (PMPs) are used on a state-by-state basis to track this activity.

Sometimes people try to acquire Schedule II drugs illegally by stealing prescription pads from doctors' offices, or by printing up phony prescription forms. Then they use those to write false prescriptions with forged signatures. These tactics are rarely successful over the course of time. Pharmacists often verify the validity of prescriptions for opioids by contacting the doctor listed as the prescribing physician. Bogus prescriptions can be stopped at this point. Pharmacists are also among the first to notice high numbers of Schedule II prescriptions being written by particular doctors. One unintended effect of this kind of monitoring is that many doctors have become reluctant to prescribe enough effective medication for patients who experience chronic pain.

For More Information

Books

Gahlinger, Paul M. Illegal Drugs: A Complete Guide to Their History, Chemistry, Use and Abuse. Las Vegas, NV: Sagebrush Press, 2001.

Kuhn, Cynthia, Scott Swartzwelder, and Wilkie Wilson. Buzzed: The Straight Facts about the Most Used and Abused Drugs from Alcohol to Ecstasy, 2nd ed. New York: W.W. Norton, 2003.

Mogil, Cindy R. Swallowing a Bitter Pill: How Prescription and Over-the-Counter Drug Abuse Is Ruining Lives—My Story. Far Hills, NJ: New Horizon Press, 2001.

Pinsky, Drew, et al. When Painkillers Become Dangerous: What Everyone Needs to Know about OxyContin and Other Prescription Drugs. Center City, MN: Hazelden Foundation, 2004.

Youngs, Bettie B., and others. A Teen's Guide to Living Drug Free. Deerfield Beach, FL: Health Communications, 2003.

Periodicals

Leinward, Donna. "Prescription Abusers Not Just after a High." USA Today (May 25, 2005).

Markon, Jerry. "25-Year Sentence for Pain Doctor." Washington Post (April 15, 2005): p. B1.

Weathermon, Ronnie A. "Controlled Substances Diversion: Who Attempts It and How." U.S. Pharmacist (December, 1999): p. 2.

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"How Can Mis-using or Abusing Rx Drugs Hurt You?" Freevibe.com.http://www.freevibe.com/Drug_Facts/prescription_effects_abuse.asp (accessed July 26, 2005).

"Kids Getting High—and Hooked—on Prescription Drugs." The Official D.A.R.E. Web site.http://www.dare.com/parents/Parents_NewsRoom/kidsgettinghigh.asp (accessed July 28, 2005).

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"National Household Survey on Drug Abuse (NHSDA)." U.S. Department of Health and Human Services, Substance Abuse and Mental Health Services Administration.http://oas.samhsa.gov/nhsda.htm (accessed July 28, 2005).

National Institute on Drug Abuse.http://www.nida.nih.gov and http://www.drugabuse.gov (both accessed July 26, 2005).

"Opioids: Beyond the ABCs." Alberta Alcohol and Drug Abuse Commission.http://corp.aadac.com/other_drugs/the_basics_about_other_drugs/opioids_beyond_abcs.asp (accessed July 26, 2005).

"Prescription Drugs." National Institute on Drug Abuse.http://www.nida.nih.gov/drugpages/prescription.html (accessed July 26, 2005).

Rubinkam, Michael. "Heroin Addicts Clamor for Scarce Medicine." Associated Press My Way News.http://apnews.myway.com/article/20050429/D89OO4JG0.html (accessed July 26, 2005).

"Teen Drug Use Declines 2003–2004—But Concerns Remain about Inhalants and Painkillers" (December 21, 2004). National Institute on Drug Abuse.http://www.nida.nih.gov/Newsroom/04/NR12-21.html (accessed July 26, 2005).

"Trouble in the Medicine Chest (I): Rx Drug Abuse Growing" (March 7, 2003). U.S. Department of Health and Human Services and SAMHSA's National Clearinghouse for Alcohol and Drug Information: Prevention Alert.http://ncadi.samhsa.gov/govpubs/prevalert/v6/4.aspx (accessed July 26, 2005).

See also: Codeine; Designer Drugs; Fentanyl; Heroin; Hydromorphone; Methadone; Morphine; Opium; Oxycodone

MEPERIDINE

OFFICIAL NAMES: Meperidine, meperidine hydrochloride, Demerol, Pethidine

STREET NAMES: Demmies

DRUG CLASSIFICATIONS: Schedule II, narcotic

OVERVIEW

Meperidine is a synthetic, opioid analgesic. An analgesic is any drug or substance that, when ingested or injected, diminishes or relieves pain. Another word for analgesic is "painkiller." Many different drugs act as analgesics. One method of classifying analgesics is to distinguish between those that require a doctor's prescription and those that do not. Medications obtainable without a doctor's prescription are known as over-the-counter (OTC) drugs. OTC analgesics are the most familiar, and include such medications as acetaminophen (Tylenol), aspirin, and ibuprofen (Advil; Midol).

The most effective and widely used prescription analgesics belong to a class of drugs known as opioids. Opioid drugs can be classified as natural, semi-synthetic, or synthetic. Natural opioids are also frequently referred to as opiates. Both terms, opiate and opioid, are derivations of opium. The drug groups were so-named because they produce effects similar to opium, which itself is a plant-based, chemically complex drug. Opium has been used throughout recorded history for both medicinal and recreational purposes.

Opium is made by drying the liquid that comes from the unripe seed capsule of the opium poppy, a flowering plant common to certain parts of the world. References to opium and its medicinal value have been found in writings dating from several thousand years ago. Up until the twentieth century, opium was prized for its ability to alleviate pain, treat diarrhea, and elevate mood. In addition to its well-established use as a treatment for pain and diarrhea, opium was touted and used as a cure for a wide range of other medical problems. In truth, however, opium had little or no real medical effects on the majority of those conditions. Instead, its ability to produce euphoria, a profound sense of well-being and calmness (elevated mood), made opium appear to be a highly effective medicine. After all, regardless of the illness or condition, a person who used opium nearly always felt better, whether or not they were truly getting better. In higher quantities, opium is also effective at inducing sleep. In fact, the scientific name for the opium poppy is Papaver somniferum, Greek for "poppy that causes sleep." In even greater quantities, opium can induce coma and death.

Although opium has genuine medical benefits, it also poses significant risks. Perhaps most important is the inherent difficulty in predicting how weak or strong opium's effects will be on any particular occasion. The concentrations of the primary active chemicals, morphine and codeine, can vary significantly from one batch of opium to the next. One reason a drug abuser might prefer prescription over illegal drugs is that they always know how much of a prescription drug they are taking. Someone who buys heroin, for instance, could be getting a nearly pure drug, or could be purchasing mostly cornstarch. Used as a medicine, opium was a risky proposition. Once the technologies in chemistry were developed, researchers in medicine and pharmacology were eager to purify the active chemicals in opium.

Along with knowledge of its desirable effects, people in ancient times were no doubt also aware of opium's undesirable effects. Serious forms of psychological and physical addiction can develop after even short-term opium use. The highly addictive nature of opium, and by extension the opioids, tends to overshadow all other issues related to the drugs. Aside from developing predictable drugs, the primary reason for previous and ongoing research in this area is to develop a powerful analgesic with as few of the harmful side effects of opium and the current opioids as possible. Addictive potential is the side effect researchers would most like to eliminate.

It was not until 1806 that a German chemist was able to isolate morphine from opium. This was a major breakthrough in pharmacology; a pure, highly effective analgesic was finally available. Unlike opium, morphine's potency is always the same, which allows for accurate scientific study of its effects. Data from studies of morphine have provided specific information about the safest and most effective dosages to use.

Morphine was the first limited success of attempts to improve on opium. The medical community was initially hopeful that, in addition to its analgesic power, morphine would be the break-through drug for treating opium addiction. In fact, morphine was successful in that regard; opium addicts that were given morphine were often cured of their addiction. However, it became painfully clear that those same patients developed an equally powerful addiction to morphine. The isolation of codeine in 1832 was also a limited success; it produces fewer side effects and is less addictive, but is much less potent than morphine.

Meperidine was first synthesized in the late 1930s, and was one of the first synthetic opioids. The fact that both morphine and codeine are still widely used, though, indicates that meperidine, along with all of the opioids produced since that time, have been only modest successes. Research continues with the hope of discovering the "perfect" opioid analgesic.

To understand the benefits and drawbacks of opioid drugs, one needs to understand their primary effects on the body; specifically, how they function as pain relievers. In the broadest sense, there are two types of pain—physical and emotional. Physical pain, while unpleasant, is necessary for survival. It serves as notification of the presence of injury or disease, which in turn prompts a person to take appropriate, possibly even life-saving action. Half of all individuals who seek medical attention report pain as their primary complaint.

Opioids produce their effects by interacting with cell-surface proteins known as opioid receptors. An opioid, whether endogenous (naturally produced by the body) or in drug form, fits into a receptor somewhat like a key in a lock. This activates the receptor and initiates complex changes in the nerve cell. Activated opioid receptors produce chemical changes that reduce the ability of a nerve cell to transmit pain signals. They also decrease the "perception" of pain by neurons in the brain. If opioids are used when one is not in pain, those same chemical changes in the brain's nerve cells can produce feelings of euphoria.

In a basic sense, both the good (analgesia) and bad (addiction) effects of opioids are caused by the same process: the interaction of drugs with nerve cells, especially those in the brain. As a neuron transmits or processes pain signals, it is functioning in an abnormal, hyperactive state. Opioids work to reduce that activity and bring the neuron back toward a more normal state. Applying the opioid effect to a neuron that is already in a normal state, however, tends to force the response of neurons in the opposite direction of pain, toward pleasure (euphoria). If neurons remain in this artificially produced state for any length of time, they become tolerant of the effect. Once the opioid is removed, the affected neurons move back toward the pain end of the spectrum, something known as the "rebound effect."

People that use meperidine for acute pain, such as after an injury, typically do not have long enough exposure to develop tolerance and addiction. People with chronic pain, however, may develop some tolerance and physical addiction in the sense that, if they stop the drug, their pain returns. Only rarely, though, do people using opioids long-term for legitimate medical reasons develop psychological addiction. A person who begins abusing an opioid drug to get high, and continues using the drug, will develop both physical and psychological tolerance and addiction. Eventually, they will need the drug not to get high, but to keep from having the pain of withdrawal. These scenarios also apply to endogenous opioids, although to a much lesser extent. For instance, athletes that produce high levels of endorphins—one of the endogenous opioids—after exercise often report that they feel depressed if they stop exercising.

CHEMICAL/ORGANIC COMPOSITION

Meperidine hydrochloride (the full name) is a synthetic opioid. It is synthesized by the reaction of chemicals not found in opium. Specifically, meperidine hydrochloride is produced by the reaction of dichlorodiethyl methylamine with benzyl cyanide, to produce ethyl 1-methyl-4-phenyl-isonipecotate hydrochloride (meperidine's chemical name). Some references to meperidine classify it as a totally synthetic opioid. Semi-synthetic opioids are produced by using one of the opiates as a starting material. Two examples of semi-synthetic opioids are hydrocodone and heroin. Hydrocodone is produced by the chemical modification of codeine, while heroin is made by chemically altering morphine.

Although morphine and meperidine are quite similar in their clinical effects, they are not that similar in chemical composition. The important chemical determinant of an opioid analgesic, however, is not its structural resemblance to morphine, but its ability to bind with and activate an opioid receptor.

INGESTION METHODS

Meperidine can be taken orally or injected. Oral forms include tablets and syrup. Dosages of tablets range from 25 mg to 100 mg meperidine per tablet. The syrup form contains 50 mg meperidine per 5 ml. The typical dosage is from 50 mg to 150 mg every three to four hours.

Injections of meperidine can be given intramuscularly (in the muscle), subcutaneously (under the skin), and intravenously (directly into the bloodstream). The body responds more readily to meperidine when it is injected, so dosages are usually about half that of the oral form, again every three to four hours. As with other opioids, intravenous administration of meperidine is often given at a low, continual dose.

Patients recovering from surgery can request that meperidine be administered through a system known as patient controlled anesthesia (PCA). This system allows a patient to administer his or her own medication in small doses. The machine has an electronic control mechanism that allows only a specific amount of meperidine to be administered by the patient each hour. PCA alleviates the need for a nurse to give the patient an intramuscular injection every three to four hours, and keeps meperidine in the body at a more constant level.

THERAPEUTIC USE

Meperidine is used for the treatment of moderate-to-severe pain, most commonly following surgery. It is sometimes given as an adjunct to anesthesia just before and during surgery. Meperidine also remains one of the more frequently used opioid analgesics in obstetric departments for severe pain during labor and delivery. Meperidine may be preferred over morphine after surgery because it produces less nausea and constipation in most people.

Meperidine is generally not recommended for use in infants and small children. Likewise, the elderly may have underlying medical conditions that present special risks with meperidine use.

Meperidine is occasionally used in outpatients for the treatment of acute pain, especially if other opioids prove ineffective. Its use for chronic pain is less accepted. Meperidine is eliminated from the body more quickly than other opioids, which means it must be taken more frequently, and its analgesic effects fluctuate more rapidly.

USAGE TRENDS

A study published in the Journal of the American Medical Association in 2000, obtained Drug Enforcement Administration (DEA) data on trends in legitimate medical use of several opioid medications, including meperidine, for the period of 1990 to 1996. In that seven-year span, meperidine use in the United States decreased by 35% (5,200 kg to 3,400 kg).

In the early 1980s, approximately 15,400 kg of meperidine were consumed worldwide each year. By 1999, that figure decreased to 12,200 kg, a 20% drop. Most of the decrease in the use of meperidine may be due to the ongoing development of other safer, longer lasting Schedule II opioids.

Scope and severity

One method of analyzing the issue of drug abuse is to compare and contrast the abuse of illegal drugs (marijuana, cocaine, etc.) with that of legal drugs (OTC and prescription medications). The majority of national and international attention and resources go toward illicit drug abuse. However, prescription drug abuse is a large and growing proportion of the complete drug abuse picture.

Each year, the National Household Survey on Drug Abuse (NHSDA)—the United States Department of Health and Human Services—collects statistical data on five drug groups: marijuana and hashish; psychotherapeutic drugs; cocaine and crack; hallucinogens; and inhalants. Psychotherapeutic drugs include stimulants, sedatives, tranquilizers, and pain relievers. Meperidine and other opioids constitute the majority of the pain relievers in that group.

In 2000, the NHSDA found 1.7% of all people 12 years and older reported nonmedical use of any psychotherapeutic medication during the previous month. More than nine million Americans over age 12 reported use at any time during the year. Those in the 18 to 25-year-old age group have the highest rates of drug abuse. In 2000, 3.6% of individuals in that age group reported nonmedical use of prescription drugs in the month prior to the date on which they were surveyed, but less than half that many, 1.6%, reported the same type of drug abuse in 1994. An estimated 1.6 million Americans used prescription pain relievers nonmedically for the first time in 1998. During the 1980s, there were generally fewer than 500,000 first-time users per year.

The study in the Journal of the American Medical Association mentioned previously also analyzed data from The Drug Abuse Warning Network (DAWN). As mentioned, the study showed a 35% decrease in the medical use of meperidine. However, use of the other four opioid drugs studied (morphine, fentanyl, oxycodone, and hydromorphone) increased, such that the group as a whole showed a cumulative increase of nearly 250%. Data collected from DAWN for the same time-period showed a 7% increase in emergency room mentions of abuse of these drugs. By comparison, the reports of abuse of illicit drugs increased 110%. Admittedly, the data collected by DAWN evaluates only one facet of the drug abuse problem—drug abuse that contributes to emergency room visits. However, from these data at least, it does not appear that a significant increase in medical use of opioid drugs resulted in a proportionate increase in abuse. Further studies looking at a broader picture of opioid analgesic abuse are needed.

Age, ethnic, and gender trends

Between 1990 and 1998, abuse of some illegal drugs among teens and young adults leveled off or decreased slightly. However, increases in new users of prescription pain relievers were reported in young teens, age 12–17, as well as in young adults age 18–25. In 2000, the NHSDA found that the youngest teens, age 12–14, reported psychotherapeutic medications as the most frequent drugs of abuse, making up 53% of the total of all drug abuse reports. Teens and young adults in the 18–25 age group reported prescription drug abuse at a rate of 36%, while 28% of those over age 26 reported that type of abuse. Most teenagers begin prescription drug abuse by taking another person's medication, usually someone from their family. Teens are also more likely than adults to be acquainted with someone illegally who sells prescription drugs like meperidine.

On the other end of the age spectrum, prescription drug abuse among older adults is also a growing concern. Persons 65 and older comprise 13% of the United States population, but consume about 33% of all prescription drugs. A study of 1,500 elderly patients found that 3% were abusing prescription drugs. Unlike people in younger age groups, however, the elderly are more likely to misuse prescription drugs than abuse them. If abuse does occur, it may begin with misuse due to inappropriate prescribing or the patient not following instructions correctly.

The NHSDA study showed that boys in the youngest age group (12–17) are more likely to experiment with illegal drugs, but girls of that age have a 20% higher rate of prescription drug abuse. In addition, for all teens of that age who abuse prescription drugs, girls are twice as likely to become addicted as boys are. Women are also more likely to abuse and become addicted to prescription drugs in the young-and middle-adult age groups. Part of this may be that women are prescribed potential drugs of abuse more often than men are. Finally, a survey of elderly persons admitted to a treatment program found that 70% were female. Of the various drugs of abuse in that group, 70% were opioids. At all age groups, whites are more likely than other racial or ethnic groups to abuse prescription drugs.

Health professionals (doctors, nurses, dentists, veterinarians, etc.) and their staff may be at risk for meperidine abuse because of their ready access to the drug. Several highly publicized cases involving health care workers who removed injectable meperidine from vials for their own use—and replaced it with some other (harmless) liquid to give to the patient—would seem to lend credence to that argument. On the other hand, one would expect health care workers to be at lesser risk due to their training and knowledge of the effects of drug abuse. In fact, the publicized cases of meperidine theft present an unbalanced picture, since health care workers do not appear to have rates of meperidine or other opioid abuse much different from the rest of the population.

MENTAL EFFECTS

As with all opioids, meperidine is capable of producing euphoria. A few people may get a mild stimulant effect and a feeling of elation. However, instead of euphoria after a meperidine dose, some people report a feeling of dysphoria—a general feeling of discomfort and restlessness—or even disorientation and confusion. Still other people may just feel drowsy, with no noticeable positive or negative effect on their mood.

It remains a misconception that opioids offer no true analgesic effect, but instead produce a type of euphoria that simply results in one not caring about one's pain. With the available detailed knowledge of the interaction between opioids and opioid receptors in the central nervous system, that myth has been dispelled. Up to a limit (usually an amount great enough to produce serious side effects), the more meperidine ingested in a single dose, the greater the analgesia and the more pronounced the mental effects.

PHYSIOLOGICAL EFFECTS

Other than analgesia, the most common physiological effects produced by medicinal quantities of meperidine are nausea, vomiting, dry mouth, dizziness, constipation, and itchy skin. These relatively harmless side effects typically disappear in most people after taking the drug for several days, or by reducing the dosage. For most people, higher doses of meperidine are more likely to produce side effects. For those who experience side effects at lower doses, any higher dose is likely to make them more pronounced.

Harmful side effects

The complication of greatest concern is respiratory depression. Opioids affect the area of the brain that controls breathing. A large enough single dose of any opioid, including meperidine, can stop breathing completely, resulting in death. Combining meperidine with another central nervous system depressant, such as alcohol or sedatives, is especially risky. While drowsiness itself is not a harmful side effect, it can be dangerous if someone drives or engages in some other activity that requires them to be alert.

Meperidine presents a higher risk for seizures than other opioids. Seizures induced by meperidine also tend to be resistant to treatment with opioid antagonists. Therefore, people with a history of seizures, and those at increased risk for first occurrence of a seizure (such as someone with head trauma) should avoid meperidine if possible. Other potential neurological side effects include tremors, delirium, and hallucinations. These side effects are uncommon, but serious. Some people may have an allergic reaction to meperidine, and severe cases can involve respiratory arrest; cold, clammy skin; generalized weakness; and unconsciousness or coma.

Patients with kidney or liver disease should exercise caution when using meperidine for any length of time. A by-product of meperidine, normeperidine, is broken down in the liver and excreted by the kidneys. Someone with impaired function of either organ may develop high levels of normeperidine, which can be toxic to the nervous system. Some people, especially the elderly, may have no history of kidney or liver disease, but can have reduced kidney and liver function following surgery. Therefore, if elderly patients must be given meperidine, the safest course may be to limit its length of use as much as possible.

Long-term health effects

Direct, negative effects on long-term health from chronic meperidine use are mostly limited to the slight possibility of central nervous system damage. There are surprisingly few other adverse health effects as far as organ or tissue damage is concerned. This is in contrast to most other abused drugs, with alcohol and tobacco being the obvious examples, and does not match the social stigma associated with opioid drugs.

Compared with other drugs, the relative lack of direct organ or tissue damage from meperidine use is counterbalanced by its high risk for abuse and addiction. High addiction potential in a drug typically means a high risk for long-term use. Long-term use can include either years of continual use or a repeated cycle of use and abstinence. The latter can be especially difficult with meperidine, given the potentially serious withdrawal symptoms associated with abruptly stopping the drug. People with meperidine or other prescription drug addiction are less likely to seek professional help than those who abuse illegal drugs. This may be due to a misperception that addiction to prescription drugs cannot or should not be as serious as illegal drug addiction. Unfortunately, self-treating an addiction usually involves abrupt cessation of the drug, with negative health effects.

The longer and more heavy the abuse, and the more suddenly the drug is ceased, the more serious and painful the withdrawal symptoms will be. Symptoms of withdrawal associated with physical addiction can include restlessness, muscle and bone pain, insomnia, diarrhea, runny nose, chills with goose bumps, and involuntary leg movements. The involuntary leg movements associated with opioid withdrawal are what originally led to the phrase "kicking the habit." In addition, the goose bumps that often occur during withdrawal originated the use of the phrase "quitting cold turkey," since the person's skin resembles that of cold turkey skin. Signs of withdrawal associated with psychological addiction include strong dysphoria (feeling badly) and a nearly uncontrollable craving for the drug.

REACTIONS WITH OTHER DRUGS OR SUBSTANCES

Some who abuse opioids are under the mistaken impression that using alcohol with the drug will enhance its effects. Like meperidine, alcohol is a cental nervous system depressant, so when both are used together, the risk for respiratory depression and death increases. Also, because alcohol impairs judgment, a drunk person is more likely to believe he can handle more of the drug than he truly can, just as many intoxicated people dangerously believe they are much better drivers than they are. Most people who end up in hospital emergency rooms after an opioid overdose were also using alcohol.

Other classes of drugs that should be avoided when using meperidine include benzodiazepines (drugs in the same class as Valium), most antihistamines, and sedatives/hypnotics (sleeping pills). Several types of antidepressants, including tricyclics, selective serotonin reuptake inhibitors (SSRIs, drugs in the same class as Prozac), and especially monoamine oxidase inhibitors (MAOIs), should be used with great caution or not at all in combination with meperidine. In general, any other central nervous system depressant should either be avoided or used under the guidance of a physician when taking meperidine.

TREATMENT AND REHABILITATION

As a Schedule II opioid narcotic, meperidine is highly addictive. Treatment for opioid overdose usually involves administration of an opioid antagonist such as Narcan (naloxone), which reverses or blocks the effects of the drug. However, in some cases, those who overdose on meperidine do not respond well to opioid antagonists.

Most people who overcome meperidine addiction do so by themselves, but some may need professional assistance. In either case, it is invaluable for someone to have the help and support of friends and family. For chronic addiction (drug use and addiction lasting more than one year), meperidine may be replaced by methadone, another opioid medication. The patient receives methadone either through a physician or through a qualified drug treatment program. In a structured setting, the patient and health care professionals have a much better chance of controlling drug use with methadone, and eventually may achieve complete abstinence. Methadone need only be taken once a day, it reduces or eliminates withdrawal symptoms and the craving for meperidine, and it has fewer side effects.

PERSONAL AND SOCIAL CONSEQUENCES

Meperidine and the other opioids do offer great personal and social medical benefits. However, these benefits must be weighed against the potential costs of abuse and addiction. The social consequences of having a broad range of effective analgesics to treat chronic pain are significant. Conditions associated with chronic pain are the largest contributors to lost work time and decreased productivity. In addition, in the long-term, many individuals with ineffectively treated pain only add to the medical costs society must bear. Therefore, doctors must weigh the risks and benefits of prescribing meperidine for each individual. Careful use of meperidine and other opioids would seem to present much greater social benefits than costs.

Personal costs—financial, physical, and emotion-al—can be huge for those individuals who abuse meperidine and become addicted. An established addiction can be expensive to maintain. Many people describe a serious opioid addiction as "all consuming"; everything in their lives eventually revolves around obtaining more of the drug. With the drug as their focus, they lose friends, alienate family members, and may be unable to hold a job. Those who are caught committing crimes to maintain their addiction may pay a very high price—loss of their freedom. Finally, whether through overdose or violence, those who abuse prescription or illicit drugs may pay the ultimate price—loss of their life.

Evidence indicates that proper meperidine prescription for legitimate medical concerns does not greatly increase the risk of addiction and abuse. Those in the medical community agree that more education is needed by both doctors and patients to help prevent the potential for abuse and addiction, so that patients truly in need are not denied access to meperidine based on misperceptions and fear. The benefits for individuals and society are great when pain is treated safely and effectively.

LEGAL CONSEQUENCES

As a Schedule II drug, meperidine is strictly controlled in the United States, as well as in other parts of the world. Its manufacture and distribution in the United States are controlled by the Food and Drug Administration (FDA) and the Drug Enforcement Administration (DEA). International control is overseen by the International Narcotic Control Board (INCB).

Hospital and community pharmacies exercise special caution when dispensing meperidine and other controlled substances. In an emergency, a doctor may choose to telephone the patient's pharmacy with the prescription. However, for medications such as meperidine, telephoned prescriptions can usually only provide a small amount of the drug, and the doctor must provide their DEA number and some relevant medical information. Refills for Schedule II medications are not allowed; a patient must obtain a new prescription from their doctor.

It is illegal to write a prescription or an order for meperidine without a valid medical license. Professionals who may legally write prescriptions or orders for meperidine include medical doctors, doctors of osteopathy, podiatrists, dentists, and veterinarians. Physicians or dentists who knowingly write multiple prescriptions for patients without a valid medical reason may end up in prison. Writing and filling bogus prescriptions for profit is an even more serious offense.

Likewise, it is illegal to obtain, or try to obtain, prescriptions for meperidine or other opioids under false pretenses (fabricated symptoms and scenarios). Nineteen states have a law (a felony in some) prohibiting patients from obtaining the same controlled substance from multiple prescribers within a limited time-period ("doctorshopping"). The perpetrators of crimes involving prescription drugs are most often white, middle-class women. Their crimes usually involve doctor-shopping and/or prescription forgery.

Many people argue that increased production of opioid drugs leads to increased rates of abuse and addiction. The national attention on burglarized pharmacies, and drugs pilfered from hospitals, seem to bolster this argument. However, studies have consistently shown that patients with chronic pain who use opioids appropriately rarely become addicted. In 2001 and 2002, a number of groups that advocate for effective pain management joined with government agencies, including the DEA, to begin a long-term effort to increase the availability of effective pain-management drugs for patients, while decreasing the chances for illegal use and abuse.

See also Codeine; Designer drugs; Fentanyl; Heroin; Morphine; Opium; Oxycodone

RESOURCES

Books

American Cancer Society. American Cancer Society's Guide to Pain Control. Atlanta: American Cancer Society Health Content Products, 2001.

Booth, Martin. Opium: A History. New York: St. Martin's Press, 1996.

Courtwright, David T. Forces of Habit: Drugs and the Making of the Modern World. Cambridge, MA: Harvard University Press, 2001.

Kuhn, Cynthia, et al. Buzzed: The Straight Facts about the Most Used and Abused Drugs from Alcohol to Ecstasy. New York:W.W. Norton and Company, Inc., 1998.

Rudgley, Richard. Essential Substances: A Cultural History of Intoxicants in Society. New York: Kodansha America, Inc., 1994.

Periodicals

Brookoff, Daniel. "Chronic Pain: 1. A New Disease?" Hospital Practice 35 (July 15, 2000): 45-59.

Brookoff, Daniel. "Chronic Pain: 2. The Case for Opioids." Hospital Practice 35 (September 15, 2000): 69-84.

Carver, Alan. "Medical Use and Abuse of Opioid Analgesics." Neurology Alert 18 (June 2000): 77.

Demott, Kathryn. "Opioids Still Worthwhile Despite Street-Drug Taint." Clinical Psychiatry News 29 (June 2001): 46.

Foster, Roxie L. "Pain Management." Journal of the Society of Pediatric Nurses 1 (July-Sept. 1996): 93.

Joranson, David E., et al. "Trends in Medical Use and Abuse of Opioid Analgesics." The Journal of the American Medical Association 282 (April 5, 2000): 1710-4.

Kettelman, Karen. "What's So Bad About Meperidine?" Nursing30 (October 2000): 20.

Mitka, Mike. "Abuse of Prescription Drugs: Is a Patient Ailing or Addicted?" The Journal of the American Medical Association283 (March 1, 2000): 1126.

Potter, Michael, et al. "Opioids for Chronic Nonmalignant Pain." Journal of Family Practice 50 (February 2001): 145.

Reidenberg, Marcus M. "Clinical Pharmacology." The Journal of the American Medical Association 273 (June 7, 1995): 1664-5.

Rich, Ben A. "Physicians' Legal Duty to Relieve Suffering." The Western Journal of Medicine 175 (September 2001): 151.

Rowbotham, David J. "Endogenous Opioids, Placebo Response, and Pain." The Lancet 357 (June 16, 2001): 1901.

Self, Timothy H. "Minimizing Risk of Meperidine Neurotoxicity." The Journal of Critical Illness 16 (May 2001): 237.

Sullivan, Louis W. "The Painkiller Prescription: Protect Use, Prevent Abuse." The Journal of Musculoskeletal Medicine 18 (September 2001): 438.

Other

Painfully Obvious: The Effects of Abusing Prescription Drugs.2002. <http://www.painfullyobvious.com>.

United Nations Office for Drug Control and Crime Prevention. (April 4, 2002). <http://www.undcp.org>.

The Vaults of Erowid: Documenting the Complex Relationship between Humans and Psychoactives. 2002. <http://www.erowid.org>.

Organizations

Drug Enforcement Administration (DEA), Information Services Section (CPI), 2401 Jefferson Davis Highway, Alexandria, VA, USA, 22301, <http://www.usdoj.gov/dea>.

National Institute on Drug Abuse (NIDA), National Institutes of Health, 6001 Executive Boulevard, Room 5213, Bethesda, MD, USA, 20892-9561, (301) 443-1124, (888) 644-6432, Information@lists.nida.nih.gov, <http://www.drugabusegov/NIDAHome.html>.

Office of Disease Prevention and Health Promotion, U.S. Department of Health and Human Services, 200 Independence Avenue SW., Room 738G, Washington, DC, USA, 20201, (202) 401-6295, <http://odphp.osophs.dhhs.gov>.

Office of FirstGov c/o GSA, 750 17th Street, N.W., Suite 200, Washington, DC, USA, 20006-4634, <http://www.whitehousedrugpolicy.gov>.

Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Dept. of Health and Human Services, 5600 Fishers Lane, Rockville,, MD, USA, 20857, (301) 443-6239, info@samhsa.gov, <http://www.samhsa.gov>.

Substance Abuse and Mental Health Services Administration (SAMHSA)/Center for Substance Abuse Treatment (CSAT), 5600 Fishers Lane, Rockville, MD, USA, 20857, (301) 443-5700, info@samsha.gov, <http://www.samhsa.gov>.

U.S. Food and Drug Administration (FDA), 5600 Fishers Lane, Rockville, MD, USA, 20857-0001, (888) 463-6332, <http://www.fda.gov>.

Scott J. Polzin, MS

Meperidine

Definition

Meperidine, available as hydrochloride salt, is a narcotic analgesic, a classification term used to describe medications capable of producing a reversible depression of the central nervous system for pain control. Because of its potential for physical and psychological dependence, meperidine is a carefully controlled substance. It is commonly referred to by one of its brand names, Demerol.

Purpose

There are several possible indications for the administration of meperidine. It is commonly used for the relief of moderate to severe pain, particularly in obstetrics. Meperidine is also widely used preoperatively, and as an adjunct to anesthesia during surgery. Meperidine is not recommended for long-term management of chronic pain, such as pain caused by cancer, because of its potential for psychological and physical dependence.

Description

Meperidine is a synthetic compound that acts as an agonist—meaning it attaches to opioid receptors in the central nervous system and stimulates physiologic activity normally stimulated by naturally occurring substances such as endorphins (short for endogenous morphine). Meperidine acts much like morphine, although constipation, suppression of the cough reflex, and smooth muscle spasm are all reduced with meperidine.

Meperidine is available in a banana-flavored syrup, in a tablet, and in a liquid form for injection. Oral meperidine tends to be less effective than the injectable form. When taking the syrup, patients should dilute it with approximately one half glass of water to reduce temporary anesthesia to the mouth and tongue.

Recommended dosage

The recommended dosage of meperidine depends on the purpose for which it is prescribed, as well as the population in whom it is administered. For example, elderly patients, or patients with underlying medical problems that increase side effects or decrease drug metabolism, should generally be given reduced dosages. Meperidine can be taken orally, in tablet or syrup form, intravenously (directly into a vein), or by injection into the muscle (intramuscularly) or connective tissue (subcutaneously).

Generally, repeated doses administered to manage pain should be given by injection intramuscularly. The subcutaneous route is acceptable for occasional administration. When given intravenously, meperidine should be diluted and administered very slowly. When taken in conjunction with phenothiazine or other tranquilizers, the dose should be decreased by as much as a half. Specific dosages are as follows.

FOR RELIEF OF MODERATE TO SEVERE PAIN.

The recommended dosage for adults for pain relief is 50-150 mg every three to four hours by oral or intramuscular route. When given intravenously through a patient-controlled analgesia (PCA) device, an initial dose of 10 mg should be administered. The PCA should be programmed to administer between 1-5 mg every 6-10 minutes. If meperidine is given continuously through an intravenous line, the dose should be adjusted based on patient response to a range of 15-35 mg an hour. Children should be given 1-1.8 mg per kg (2.2 pounds) intramuscularly or subcutaneously.

FOR PREOPERATIVE MEDICATION.

Adults may be given 50-100 mg of meperidine intramuscularly, or subcutaneously 30-90 minutes prior to surgery. Children's dosages should be reduced to 1-2 mg per kg through the same routes.

For obstetric pain control. The recommended dosage for control of regular (not sporadic) pain in this setting is 50-100 mg every 1-3 hours intramuscularly or subcutaneously.

Precautions

Other patients who should avoid meperidine use include those with previous hypersensitivity to narcotics, or those with underlying respiratory problems. Meperidine, even in recommended therapeutic doses, can decrease the respiratory drive. Conditions such as asthma or chronic obstructive pulmonary disease may increase the likelihood of respiratory difficulty. Meperidine can also impair judgment, and should not be used in individuals engaging in activities that require alertness, such as driving.

Because its effects on a fetus are unknown, meperidine is not recommended in pre-labor stage pregnant women. Even in labor, when it may be indicated for pain control, meperidine may cause respiratory depression of the mother and her baby, particularly premature babies. Meperidine is excreted in breast milk, and, if needed, should be administered several hours before breastfeeding to minimize ingestion by the infant.

Side effects

The most common adverse effects of meperidine are lightheadedness, dizziness, sedation, nausea and/or vomiting, and sweating. Less common, but more severe, side effects include respiratory depression and abnormally low blood pressure.

Interactions

Individuals who are taking, or who have recently taken, drugs called monoamine oxidase (MAO) inhibitors (a class of antidepressants), should not be given meperidine. Reactions have been reported in this population that are characterized by a variety of signs and symptoms including respiratory distress, coma, abnormally low or abnormally high blood pressure, hyperexcitability, and even death. If administration of a narcotic is required, it should be given in small, gradually increasing test doses under careful supervision.

Adverse effects such as respiratory depression and decreased blood pressure are more common when meperidine is administered in conjunction with other narcotic analgesics, anesthetics, phenothiazines, sedatives, or any other type of drug that suppresses the central nervous system. Alcohol should also be avoided.

Tamara Brown, R.N.

KEY TERMS

Agonist

—A drug that binds to cell receptors and stimulates activities normally stimulated by naturally occurring substances.

Endorphin

—Short for endogenous morphine, it is a naturally occurring substance that binds to opioid receptors in the brain.

Narcotic analgesic

—A classification of medications that relieves pain by temporarily depressing the central nervous system.

Opioid

—A drug that possesses some properties characteristic of opiate narcotics but not derived from opium.

Patient controlled analgesic (PCA)

—A device resembling an intravenous pump that allows patients to self-medicate within pre-established dosage parameters for pain control.

pethidine (peth-i-deen) n. a potent opioid analgesic drug with mild sedative action, administered by mouth or injection to relieve moderate or severe pain of short duration (including that associated with childbirth).