Cidofovir

Cidofovir is a prescription medication used to treat cytomegaloviral (CMV) retinitis, which is a viral inflammation of the eye, in people with acquired immune deficiency syndrome (AIDS).

Cidofovir belongs to a group of drugs called antiviral agents. These work by stopping the growth of viruses that cause infections.

This medication is available in an injectable form to be given directly into a vein (IV) by a healthcare professional.

Common side effects of cidofovir include headache, diarrhea, stomach pain, constipation, sore mouth or tongue, joint and muscle pain, coughing, fever, and chills.

Cidofovir can also cause dizziness. Do not drive or operate heavy machinery until you know how cidofovir affects you.

Cidofovir is a prescription medication used to treat cytomegaloviral (CMV) retinitis, which is a viral inflammation of the eye, in people with acquired immune deficiency syndrome (AIDS).

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Cidofovir may be found in some form under the following brand names:

• Vistide

Serious side effects have been reported with cidofovir. See the “Cidofovir Precautions” section.

Common side effects of cidofovir include the following:

• headache
• diarrhea
• stomach pain
• constipation
• sore mouth or tongue
• joint and muscle pain
• coughing
• fever
• chills

This is not a complete list of cidofovir side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

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

Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• aminoglycoside antibiotics, including tobramycin (Tobi, Tobrex), gentamicin (Gentak, Garamycin), amikacin (Amikin)
• amphotericin B (Ambisome, Amphotec)
• foscarnet (Foscavir)
• non-steroidal anti-inflammatory agents (NSAIDs), including ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn)
• pentamidine (NebuPent)
• vancomycin (Vancocin)
• vitamins
• zidovudine (Combivir, Retrovir, Trizivir)

This is not a complete list of cidofovir drug interactions. Ask your doctor or pharmacist for more information.

Serious side effects have been reported with cidofovir including the following:

• Uveitis and iritis. Tell your healthcare provider right away if you have some or all of the following symptoms of inflammation of parts of the eye:
  • eye pain
  • sensitivity to light
  • decreased vision
• Allergic reactions. Tell your healthcare provider right away if you have some or all of the following symptoms of inflammation of parts of the eye:
  • skin rash
  • itching of the skin

Cidofovir can cause dizziness. Do not drive or operate heavy machinery until you know how cidofovir affects you.

Do not take cidofovir if you:

• are allergic to cidofovir or to any of its ingredients
• are allergic to probenecid or sulfa-containing medications
• have severe renal impairment or are at increased risk for kidney damage

Medications can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of cidofovir, there are no specific foods that you must exclude from your diet when receiving this medication.

Before taking cidofovir, tell your doctor about all of your medical conditions. Especially tell your doctor if you:

• are allergic to cidofovir or to any of its ingredients
• are allergic to probenecid or sulfa-containing medications
• have liver problems
• have kidney problems, including diabetes
• are pregnant or breastfeeding

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X - are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Cidofovir falls into category C. In animal studies, pregnant animals were given this medication and had some babies born with problems. No well-controlled studies have been done in humans. Therefore, this medication may be used if the potential benefits to the mother outweigh the potential risks to the unborn child.

Tell your doctor if you are breastfeeding or plan to breastfeed.

It is not known if cidofovir crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. Your doctor and you will decide if the benefits outweigh the risk of using cidofovir.

Take cidofovir exactly as prescribed.

This medication is available in an injectable form to be given directly into a vein (IV) by a healthcare professional.

If you miss a dose, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of cidofovir at the same time.

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dose your doctor recommends may be based on the following:

• other medical conditions you have
• other medications you are taking
• your weight

The recommended dose of cidofovir for the treatment of cytomegaloviral retinitis is 5 mg/kg. It is administered as an infusion over 1 hour every 2 weeks.

If you take too much cidofovir, call your healthcare provider or local Poison Control Center or seek emergency medical attention right away.

If cidofovir is administered by a healthcare provider in a medical setting, it is unlikely that an overdose will occur. However, if overdose is suspected, seek emergency medical attention.

Keep this and all medicines out of the reach of children.

WARNING:

RENAL IMPAIRMENT IS THE MAJOR TOXICITY OF VISTIDE. CASES OF ACUTE RENAL FAILURE RESULTING IN DIALYSIS AND/OR CONTRIBUTING TO DEATH HAVE OCCURRED WITH AS FEW AS ONE OR TWO DOSES OF VISTIDE. TO REDUCE POSSIBLE NEPHROTOXICITY, INTRAVENOUS PREHYDRATION WITH NORMAL SALINE AND ADMINISTRATION OF PROBENECID MUST BE USED WITH EACH VISTIDE INFUSION. RENAL FUNCTION (SERUM CREATININE AND URINE PROTEIN) MUST BE MONITORED WITHIN 48 HOURS PRIOR TO EACH DOSE OF VISTIDE AND THE DOSE OF VISTIDE MODIFIED FOR CHANGES IN RENAL FUNCTION AS APPROPRIATE. VISTIDE IS CONTRAINDICATED IN PATIENTS WHO ARE RECEIVING OTHER NEPHROTOXIC AGENTS.

NEUTROPENIA HAS BEEN OBSERVED IN ASSOCIATION WITH VISTIDE TREATMENT. THEREFORE, NEUTROPHIL COUNTS SHOULD BE MONITORED DURING VISTIDE THERAPY.

VISTIDE IS INDICATED ONLY FOR THE TREATMENT OF CMV RETINITIS IN PATIENTS WITH ACQUIRED IMMUNODEFICIENCY SYNDROME. IN ANIMAL STUDIES CIDOFOVIR WAS CARCINOGENIC, TERATOGENIC AND CAUSED HYPOSPERMIA.