Streptozocin

Definition

Streptozocin is one of the anticancer (antineoplastic) drugs called alkylating agents. It is available in the U.S. under the brand name Zanosar.

Purpose

Streptozocin is primarily used to treat cancer of the pancreas, specifically advanced islet-cell carcinoma .

Description

Streptozocin chemically interferes with the synthesis of the genetic material (DNA) of cancer cells, which prevents these cells from being able to reproduce.

Recommended dosage

Streptozocin is given by injection. The dosage prescribed varies widely depending on the patient, the cancer being treated, and whether or not other medications are also being taken.

Precautions

Streptozocin carries a risk of renal (kidney) toxicity. While receiving streptozocin, patients are encouraged to drink extra fluids, since this can increase the amount of urine passed and help prevent kidney problems.

Streptozocin may cause an allergic reaction in some people. Patients with a prior allergic reaction to streptozocin should not take this medication.

Streptozocin also may cause serious birth defects if either the man or the woman is taking this drug at the time of conception or if the woman takes this drug during pregnancy. Streptozocin also may cause miscarriage.

It is not known whether streptozocin is passed from mother to child through breast milk. However, since many drugs are excreted in breast milk and since streptozocin has the potential to adversely affect an infant, breast feeding is not recommended while this medication is being taken.

Streptozocin suppresses the immune system (by damaging white blood cells) and interferes with the normal functioning of certain organs and tissues. For these reasons, it is important that the prescribing physician is aware of any of the following pre-existing medical conditions:

• a current case of, or recent exposure to, chicken pox
• diabetes mellitus
• herpes zoster (shingles)
• a current case, or history of, gout or kidney stones
• all current infections
• kidney disease
• liver disease

Also, because streptozocin damages white blood cells and platelets, patients taking this drug must exercise extreme caution to avoid contracting any new infections or sustaining any injuries that result in bruising or bleeding.

Side effects

The common side effects of streptozocin include:

• fatigue
• loss of appetite (anorexia )
• nausea and vomiting
• increased susceptibility to infection and bleeding
• swelling of the feet or lower legs
• unusual decrease in urination
• temporary hair loss (alopecia )

Diarrhea is a less common side effect that may also occur.

Because streptozocin can damage the kidneys, liver, white blood cells, and platelets, patients taking this medication should be closely monitored for evidence of these adverse side effects. Laboratory tests, including renal function, urinalysis, complete blood count, and liver function, should be done at frequent intervals (approximately weekly) during drug therapy. If evidence of these adverse side effects is found, treatment with streptozocin may be discontinued or the dose may be decreased.

Interactions

Streptozocin should not be taken in combination with any prescription drug, over-the-counter drug, or herbal remedy without prior consultation with a physician. It is particularly important that the prescribing physician be aware of the use of any of the following drugs:

• anti-infection drugs
• carmustine (an anticancer drug)
• cisplatin (an anticancer drug)
• cyclosporine (an immunosuppressive drug)
• deferoxamine (used to remove excess iron from the body)
• gold salts (used for arthritis)
• inflammation or pain medication other than narcotics
• narcotic pain medication containing acetaminophen (Tylenol) or aspirin
• lithium (used to treat bipolar disorder)
• methotrexate (an anticancer drug also used for rheumatoid arthritis and psoriasis)
• penicillamine (used to treat Wilson's disease and rheumatoid arthritis)
• phenytoin (an anticonvulsant)
• plicamycin (an anticancer drug)
• tiopronin (used to prevent kidney stones)

See Also Pancreatic cancer, endocrine

Paul A. Johnson, Ed.M.

KEY TERMS

Antineoplastic

—A drug that prevents the growth of a neoplasm by interfering with the maturation or proliferation of the cells of the neoplasm.

Neoplasm

—New abnormal growth of tissue.