Zalcitabine can cause serious nerve problems (peripheral neuropathy), rare swelling of the pancreas (pancreatitis), rare metabolic problems (lactic acidosis), and rare liver problems, especially in those infected with the hepatitis B virus. Some of these problems may be fatal.

Seek immediate medical attention if you experience any of the following symptoms: dark urine, persistent nausea/vomiting, stomach/abdominal pain, deep/rapid breathing, unusual weakness, yellowing of eyes/skin, or pain/numbness/tingling/burning feelings in the arms/legs.

This drug, used in combination with other medications, helps to control your HIV infection, thereby improving your quality of life. It also lowers your risk of getting HIV disease complications (e.g., opportunistic infections, cancer). However, this drug is not a cure for HIV infection, and it does not prevent the spread of HIV to others through sexual contact or blood contamination (e.g., sharing needles).

Zalcitabine is an antiviral drug (nucleoside reverse transcriptase inhibitor-NRTI) that works by slowing the growth of the human immunodeficiency virus (HIV). Zalcitabine is sometimes called "ddC."

One group of HIV medications (the nucleoside/nucleotide reverse transcriptase inhibitors-NRTIs such as zidovudine and lamivudine) are very useful. However, NRTIs are recommended to be used in combination with other groups of HIV medications in order to be effective. Consult your doctor or pharmacist for more details.

Take this medication by mouth with or without food, usually every 8 hours or as directed by your doctor.

Do not take this medication for at least 1 hour before or after taking products that contain magnesium or aluminum such as quinapril, certain forms of didanosine, and antacids. These products bind with zalcitabine, preventing its full absorption. Consult your pharmacist if you have any questions.

Dosage is based on your medical condition and response to therapy.

It is very important to continue taking this medication and other anti-HIV medications exactly as prescribed by your doctor.

This medication works best when the amount of drug in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals. To help you remember, use it at the same times each day. Do not skip any doses.

Do not take more or less of this drug than prescribed or stop taking it or other HIV medicines, even for a short time, unless directed to do so by your doctor. Skipping or changing your dose without approval from your doctor may cause serious problems, such as increasing the amount of the virus in your body, making the virus more difficult to treat (developing resistance), or making side effects worse.

See also Warning section.

Vomiting/nausea, headache, diarrhea/constipation, abdominal pain, or sores in the mouth/throat may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she as judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these unlikely but serious side effects occur: unusual fatigue, painful swallowing, fast/pounding heartbeat, new signs of infection (e.g., fever, persistent sore throat), easy bruising/bleeding, mental/mood changes, muscle/joint pain, seizures, swelling of the ankles/feet, shortness of breath, increased thirst/urination, change in the amount of urine.

Changes in body fat may occur while you are taking this medication (e.g., 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.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking zalcitabine, tell your doctor or pharmacist if you are allergic to it; or to other HIV medications (e.g., zidovudine, didanosine); or if you have any other allergies.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: numbness/tingling of arms/legs (peripheral neuropathy), hepatitis B infection, kidney disease, liver disease, certain heart problems (e.g., cardiomyopathy, congestive heart failure), pancreas problems (pancreatitis), diabetes, high blood fat level (triglycerides), alcohol use.

Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be at greater risk for side effects while using this drug.

This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

It is not known if zalcitabine passes into breast milk. Because breast milk can transmit HIV, do not breast-feed.

Your healthcare professionals (e.g., doctor or pharmacist) may already be aware of any possible drug interactions and may be monitoring you for it. Do not start, stop or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious interactions may occur: didanosine, lamivudine, pentamidine injection, stavudine.

If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting zalcitabine.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: cimetidine, probenecid, drugs that may be harmful to your kidneys (e.g., aminoglycosides such as gentamicin, amphotericin B, foscarnet), other drugs that may cause peripheral neuropathy (e.g., cisplatin, dapsone, disulfiram, gold therapy, isoniazid, nitrofurantoin, phenytoin, ribavirin, vincristine).

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US national poison hotline at 1-800-222-1222. Canadian residents should call their local poison control center directly.

To decrease your risk of spreading HIV/other sexually transmitted diseases, always use an effective barrier method (e.g., latex condoms/dental dams) during sexual activity. Consult your doctor or pharmacist for more details.

Do not share this medication with others.

Laboratory and/or medical tests (e.g., complete blood counts, kidney or liver function tests, amylase, triglyceride levels) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.

Keep all medical and laboratory appointments.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

Store at room temperature between 59-86 degrees F (15-30 degrees C) in a tightly closed container, away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

MEDICAL ALERT: Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).

Information last revised September 2009 Copyright(c) 2009 First DataBank, Inc.