Combivir

Combivir is a prescription medication used to treat human immunodeficiency virus (HIV) infection. It is a single tablet containing 2 medications, lamivudine and zidovudine. They belong to a group of drugs called nucleoside reverse transcriptase inhibitors (NRTIs) which stop the virus from replicating.

This medication comes in tablet form and is usually taken twice daily, with or without food.

Common side effects include nausea, vomiting, headaches, and tiredness.

Combivir is a prescription medicine used to treat HIV infection. HIV (human immunodeficiency virus) is the virus that causes AIDS (acquired immune deficiency syndrome).

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

• ViiV Healthcare Company

Consult your doctor at your next visit if any of the following undesirable events occur:

• signs of an allergic reaction such as rash, hives, itching, swelling, and difficulty breathing or swallowing
• signs of lactic acidosis such as muscle or stomach pain, extreme weakness or tiredness, feeling cold, enlarged or tender liver, and weight loss
• and frequent infections

Commonly reported side effects include:

• nausea and vomiting
• headaches
• fatigue
• diarrhea
• a general feeling of being unwell

Tell your healthcare provider about any side effect that is bothersome or does not go away.

This is not a complete list of this medication's side effects. Ask your doctor or pharmacist for more information.

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

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

• phenytoin (Dilantin, Phenytek)
• valproic acid (Depakene, Depakote, Stavzor)
• oxazepam (Serax)
• lorazepam (Ativan)
• codeine
• morphine
• methadone (Dolophine, Methadose)
• rifampin (Rifadin)
• rifapentine (Priftin)
• indomethacin
• ketoprofen
• naproxen
• cimetidine (Tagamet)
• probenecid (Benuryl) 
• co-trimoxazole
• atovaquone (Mepron)
• amphotericin
• interferon medications
• vincristine
• vinblastine
• doxorubicin (Adriamycin, Doxil)
• clarithromycin
• ribavirin (Copegus, Rebetol, Ribasphere, Virazole)
• zalcitabine (Hivid)
• stavudine (Zerit)
• ganciclovir (Cytovene)
• fluconazole (Diflucan)
• nelfinavir (Viracept)
• ritonavir (Norvir)

Combivir should not be taken with drugs containing lamivudine, zidovudine, or emtricitabine, including EPIVIR (lamivudine), EPIVIR-HBV (lamivudine), RETROVIR (zidovudine), EPZICOM (abacavir sulfate and lamivudine), TRIZIVIR (abacavir sulfate, lamivudine, and zidovudine), ATRIPLA (efavirenz, emtricitabine, and tenofovir), EMTRIVA (emtricitabine), or TRUVADA (emtricitabine and tenofovir).

This is not a complete list of Combivir drug interactions. Ask your healthcare provider or pharmacist for more information.

Do not use Combivir:

• If you previously had an allergic reaction to Combivir or to any of the ingredients in the product.
• If you have a very low red blood cell count (anemia) or very low white blood cell count (neutropenia).

Combivir should not be taken with drugs containing lamivudine, zidovudine, or emtricitabine, including EPIVIR (lamivudine), EPIVIR-HBV (lamivudine), RETROVIR (zidovudine), EPZICOM (abacavir sulfate and lamivudine), TRIZIVIR (abacavir sulfate, lamivudine, and zidovudine), ATRIPLA (efavirenz, emtricitabine, and tenofovir), EMTRIVA (emtricitabine), or TRUVADA (emtricitabine and tenofovir)

Combivir may cause a decrease in certain types of blood counts (including red blood cells, white blood cells and platelets) and an increase in certain liver enzymes.

Changes in body fat have been seen in some patients taking antiretroviral therapy. These changes may include increased amounts of fat in the upper back and neck ("buffalo hump"), breasts, and around the trunk. Loss of fat from the legs, arms, and face may also happen. The cause and long-term health effects of these conditions are not known at this time.

Changes in your immune system (Immune Reconstitution Syndrome) can happen when you start taking HIV medicines. Your immune system may get stronger and begin to fight infections that have been hidden in your body for a long time, or you could develop an autoimmune disease in which your immune system reacts against your own body (e.g. Grave's disease (which affects the thyroid gland), Guillain-Barre syndrome (which affects the nervous system) or polymyositis (which affects the muscles) and it may develop at any time, sometimes months later after the start of HIV therapy). Sometimes symptoms can be severe, so if you develop high temperature (fever), joint or muscle pain, redness, rash, swelling, or fatigue or any new symptoms contact your doctor right away.

The class of medicines to which Combivir belongs (NRTIs) can cause a condition called lactic acidosis (excess of lactic acid in your blood), together with an enlarged liver. Symptoms of lactic acidosis include feeling of weakness, loss of appetite, sudden unexplained weight loss, upset stomach and difficulty breathing. This rare but serious side effect occurs more often in women. If you have liver disease you may also be more at risk of getting this condition. While you are being treated with Combivir your doctor will monitor you closely for any signs that you may be developing lactic acidosis.

Medicines 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 Combivir there are no specific foods that you must exclude from your diet.

Before receiving Combivir, talk to your doctor or pharmacist if you:

• ever had to stop taking this or another medication for this illness because you were allergic to them or they caused problems.
• had, or you have, any diseases of the kidney.
• had, or you have, any diseases of the liver, particularly hepatitis B infection.
• had, or you have, very low red blood cell count (severe anemia) or very low white blood cell count (neutropenia).
• are taking ribavarin as it could cause or worsen anemia (symptoms of tiredness, shortness of breath). Your doctor will advise whether you should stop taking this medication.
• 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.

This medication 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 healthcare provider if you are breastfeeding or plan to breastfeed.

It is recommended that HIV-infected women do not breastfeed their infants in order to avoid transmission of HIV. The active substances in Combivir are found in human breast milk. Mothers taking Combivir should not breastfeed their infants.

Combivir comes as a tablet to be taken by mouth, usually twice daily. It can be taken with or without food.

If you forget to take your medicine, take it as soon as you remember. Then continue as before.

Do not double dose to make up for a forgotten dose.

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:

• the condition being treated
• other medical conditions you have
• other medications you are taking
• how you respond to this medication
• your weight
• your height
• your age
• your gender

For adults and adolescents weighing ≥30 kilograms, the recommended dose is one tablet (equal to 150 mg lamivudine, 300 mg zidovudine) twice daily.

For children, the recommended dose should be based on body weight not to exceed adult doses.

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

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to Combivir.

WARNING: HEMATOLOGIC TOXICITY, MYOPATHY, LACTIC ACIDOSIS, EXACERBATIONS OF HEPATITIS B

Zidovudine, one of the 2 active ingredients in this medication, has been associated with hematologic toxicity including neutropenia and anemia, particularly in patients with advanced HIV-1 disease.

Prolonged use of zidovudine has been associated with symptomatic myopathy.

Lactic acidosis and hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues alone or in combination, including lamivudine, zidovudine, and other antiretrovirals. Suspend treatment if clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity occur.

Acute exacerbations of hepatitis B have been reported in patients who are co-infected with hepatitis B virus (HBV) and HIV-1 and have discontinued lamivudine, which is one component of this medication. Hepatic function should be monitored closely with both clinical and laboratory follow-up for at least several months in patients who discontinue this medication and are co-infected with HIV-1 and HBV. If appropriate, initiation of anti-hepatitis B therapy may be warranted.