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Generic name: zalcitabine [ zal-SITE-ah-been ]
Brand name: Hivid

Zalcitabine may infrequently cause severe side effects, which could be fatal. Zalcitabine can cause severe nerve problems (peripheral neuropathy), and should be used with extreme caution in those who already suffer from this disorder. It may rarely cause swelling of the pancreas (pancreatitis). Tell your doctor immediately if vomiting, stomach/abdominal pain, or persistent nausea occur, as zalcitabine may need to be stopped until you can be checked. Severe and sometimes fatal lactic acidosis or severe liver disease may also occur. Rarely, fatal liver failure has occurred in those with hepatitis B infection while using zalcitabine. Zalcitabine should be used with caution if you have a hepatitis B infection. Tell your doctor immediately if tingling/numbness of the hands and feet, dark urine, yellowing of eyes/skin, rapid breathing, muscle aches, or unusual drowsiness occurs.

Zalcitabine is used for:

Treating HIV infection. It is used in combination with other medicines.

Zalcitabine in a nucleoside reverse transcriptase inhibitor. It works by blocking the growth of HIV.

Do NOT use zalcitabine if:

  • you are allergic to any ingredient in zalcitabine
  • you have lactic acidosis (a metabolic disorder) or certain liver problems (eg, enlarged liver, liver steatosis, abnormal liver function tests)
  • you are taking lamivudine or didanosine

Contact your doctor or health care provider right away if any of these apply to you.

Before using zalcitabine:

Some medical conditions may interact with zalcitabine. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have a nervous system disease (eg, peripheral neuropathy); a history of liver disease, including hepatitis B; kidney problems; diabetes; heart problems (eg, cardiomyopathy, congestive heart failure); AIDS; high triglyceride levels; or inflammation of the pancreas
  • if you have had unusual weight loss, are very overweight, have certain abnormal blood levels (eg, increased serum amylase, very low CD4 cell count), or if you regularly consume alcoholic beverages

Some MEDICINES MAY INTERACT with zalcitabine. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Pentamidine or zidovudine because side effects, such as increased risk of swelling or irritation of the pancreas, may occur
  • Lamivudine because effectiveness of zalcitabine may be decreased
  • Chloramphenicol, cisplatin, dapsone, disulfiram, ethionamide, glutethimide, gold-based medicines (eg, gold sodium thiomalate), other nucleoside analogs (eg, didanosine), phenytoin, ribavirin, vincristine, hydralazine, iodoquinol, isoniazid, metronidazole, or nitrofurantoin because risk of severe nerve problems may be increased
  • Aminoglycosides (eg, gentamicin), amphotericin, cimetidine, magnesium or aluminum-containing antacids, or probenecid because risk of side effects or toxic effects may be increased

This may not be a complete list of all interactions that may occur. Ask your health care provider if zalcitabine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use zalcitabine:

Use zalcitabine as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take zalcitabine on an empty stomach at least 1 hour before or 2 hours after eating.
  • Zalcitabine must be taken with other medicines that treat HIV infection to be effective.
  • Do not take zalcitabine at the same time you take antacids containing magnesium or aluminum.
  • Continue to use zalcitabine even if you feel well. Do not miss any doses.
  • If you miss a dose of zalcitabine, take it as soon as you remember. If it is within 2 hours of your next dose, skip the missed dose and go back to your regular dosing schedule. It is important not to miss doses of zalcitabine. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use zalcitabine.

Important safety information:

  • Do not exceed the recommended dose without checking with your doctor. Exceeding the prescribed dose of zalcitabine may not provide additional benefits, and may increase the risk of side effects.
  • When your medicine supply begins to run low, get more from your doctor or pharmacy as soon as possible. The virus may develop resistance to zalcitabine if you stop taking it, even for a short period of time, and may become harder to treat.
  • If you experience numbness, tingling, or pain in the hands or feet, report these symptoms to your health care provider. Parents should closely watch their children for these symptoms if they are taking this medication. Inform your health care provider if your child has ever experienced any of these symptoms.
  • Contact your health care provider if severe nausea, vomiting, or stomach pain occurs.
  • Zalcitabine is not a cure for HIV infection and patients may continue to acquire illnesses/infections associated with HIV infection. Remain under the care of your health care provider.
  • Zalcitabine offers no protection from the transmission of HIV to others through sexual contact or blood contamination. Use barrier forms of contraception (eg, condoms) if you are infected with HIV.
  • Changes in body fat may occur while you are taking zalcitabine (eg, increased fat in the upper back and stomach areas, decreased fat in the arms and legs). The cause and long-term effects of these changes are unknown. Discuss the risks and benefits of therapy with your doctor, as well as the possible role of exercise to reduce this side effect.
  • LAB TESTS will be performed to monitor your progress. Be sure to keep all doctor and lab appointments.
  • Use an effective form of birth control while taking zalcitabine.
  • PREGNANCY AND BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using zalcitabine during pregnancy. It is unknown if zalcitabine is excreted in breast milk. HIV-infected mothers should not breast-feed their infants because of the risk of transmitting the HIV infection or zalcitabine to the baby.

Possible side effects of zalcitabine:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Constipation; diarrhea; fatigue; headache; itching; loss of appetite; nausea; shift in body fat to stomach and upper back; tiredness.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); convulsions; fast, shallow breathing; feeling cold; heart problems; lactic acid imbalance (slow or irregular heartbeat; dizziness; lightheadedness); liver inflammation (liver tenderness; weakness; fatigue); numbness, tingling, burning, or sharp shooting pains in arms, hands, legs, and feet; pain on swallowing; persistent or severe nausea; severe muscle pain or cramping; sores in mouth or throat; stomach pain; swelling of the hands or feet; vomiting; weakness or exhaustion.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center ( ), or emergency room immediately.

Proper storage of zalcitabine:

Store tablets at room temperature, 59 to 86 degrees F (15 to 30 degrees C), in a tightly-closed container. Store away from heat, moisture, and light. Do not store in the bathroom. Keep zalcitabine out of the reach of children and away from pets.

General information:

  • If you have any questions about zalcitabine, please talk with your doctor, pharmacist, or other health care provider.
  • Zalcitabine is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information is a summary only. It does not contain all information about zalcitabine. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.