Common uses

Lamivudine and zidovudine are antiviral medications. They are in a group of human immunodeficiency virus (HIV) medicines called reverse transcriptase inhibitors. This medication helps keep the HIV virus from reproducing in the body.
Combivir is used to treat HIV, which causes the acquired immunodeficiency syndrome (AIDS). Combivir is not a cure for HIV or AIDS.
Combivir may also be used for purposes other than those listed in this medication guide.

Before using

Do not use Combivir if you are allergic to lamivudine or zidovudine. Combivir should not be taken together with any other medications that contain either of these two drugs. This includes Epivir, Retrovir, Epzicom (abacavir and lamivudine), and Trizivir (abacavir, lamivudine, zidovudine).
Before taking Combivir, tell your doctor if you are allergic to any drugs, or if you have:
• kidney disease;
• liver disease;
• pancreatitis;
• bone marrow suppression; or
• problems with your muscles.
If you have any of the conditions listed above, you may not be able to use Combivir or you may need a dosage adjustment or special tests during treatment.
Combivir may cause lactic acidosis (the build up of lactic acid in the body). Lactic acidosis symptoms can start slowly and gradually get worse. Symptoms include unusual muscle pain and weakness, trouble breathing, fast or uneven heart rate, nausea, vomiting, stomach pain, and numbness or cold feeling in your arms or legs. Call your doctor at once if you have any of these symptoms, even if they are only mild. Early signs of lactic acidosis generally get worse over time and this condition can be fatal. FDA pregnancy category C. Combivir may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. HIV can be passed to the baby if the mother is not properly treated during pregnancy. Take all of your HIV medicines as directed to control your infection while you are pregnant.
Your name may need to be listed on an antiviral pregnancy registry when you start using Combivir.
You should not breast-feed while you are using Combivir. Women with HIV or AIDS should not breast-feed at all. Even if your baby is born without HIV, you may still pass the virus to the baby in your breast milk. Do not give this medication to a child younger than 12 years old.

Directions

Combivir is taken by mouth as a tablet. The normal adult dose is one tablet, two times a day. Each tablet includes 300 milligrams (mg) of zidovudine (Retrovir) and 150 mg of lamivudine (Epivir).
Combivir can be taken with food, or between meals.
The dosage of lamivudine should be reduced for people who weigh less than 50 kilograms (110 pounds). People who weigh less than 110 pounds should normally not take Combivir.

Cautions

Zidovudine, one of the ingredients of this drug, has caused severe blood problems including a decrease in red blood cells (anemia) and white blood cells (neutropenia). This occurs more frequently in people with advanced HIV disease (AIDS). Seek immediate medical attention if you develop signs of anemia (new/severe tiredness, breathing problems, weakness, bluish fingernails/lips, pale skin, fast heartbeat). Low white blood cells can make you more likely to get serious (sometimes fatal) infections. Seek immediate medical attention if you develop a new fever, chills, cough, breathing problems, loss of appetite, weight loss, new diarrhea, sore throat.
This medication may also cause muscle problems (myopathy). Seek immediate medical attention if you develop symptoms of myopathy (e.g., decrease in muscle size (wasting), muscle weakness/pain/tenderness).
Rarely, zidovudine and lamivudine have caused a severe (sometimes fatal) liver and blood problem (lactic acidosis). Tell your doctor immediately if you develop symptoms of liver problems (persistent nausea, stomach/abdominal pain, dark urine, yellowing eyes/skin) or lactic acidosis (rapid breathing, drowsiness, muscle aches).
If you have hepatitis B infection along with HIV, you may have a serious worsening of hepatitis symptoms if you stop taking lamivudine. Talk with your doctor before stopping this medication. Your doctor will perform liver function tests for several months after you stop lamivudine. Tell your doctor immediately if you develop symptoms of worsening liver problems.

Possible side effects

Stop using this medication and get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have any of these serious side effects:
• muscle pain and weakness, trouble breathing, fast or uneven heart rate, nausea, vomiting, stomach pain, numbness or cold feeling;
• fever, chills, body aches, flu symptoms;
• easy bruising or bleeding, unusual weakness, pale skin;
• nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
• sudden and severe stomach pain with nausea, vomiting, fever, chills, and rapid pulse; or
• white patches or sores inside your mouth or on your lips.
Less serious side effects may be more likely to occur, such as:
• changes in the shape or location of body fat (especially in your arms, legs, face, neck, breasts, and trunk);
• nausea, vomiting, diarrhea, loss of appetite;
• sleep problems (insomnia), strange dreams;
• headache, dizziness; or
• cough, runny or stuffy nose.
Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

If you take too much

Seek emergency medical attention if you think you have used too much of this medicine.
Symptoms of a Combivir overdose may include nausea, vomiting, headache, dizziness, drowsiness, confusion, and seizure (convulsions).

Additional information

Combivir should not be taken together with any other medications that contain either of these two drugs. This includes Epivir, Retrovir, Epzicom (abacavir and lamivudine), and Trizivir (abacavir, lamivudine, zidovudine).
Avoid contact with people who have colds, the flu, or other contagious illnesses. Contact your doctor immediately if you develop signs of infection.
Avoid having unprotected sex or sharing needles, razors, or toothbrushes. Taking this medication will not prevent you from passing HIV to other people. Talk with your doctor about safe methods of preventing HIV transmission during sex, such as using a condom and spermicide. Sharing drug or medicine needles is never safe, even for a healthy person.
Avoid drinking alcohol while taking Combivir. Alcohol may increase the risk of damage to the pancreas and/or liver.

Drug interactions

Before taking this medication, tell your doctor if you are using any of the following drugs:
• cancer treatments;
• stavudine (Zerit);
• doxorubicin (Adriamycin);
• zalcitabine (Hivid);
• ganciclovir (Cytovene);
• interferon-alfa (Roferon, Intron, Rebetron);
• trimethoprim (Bactrim, Proloprim, Septra, Trimpex); or
• ribavirin (Rebetol, Ribasphere, Copegus Virazole).
There may be other drugs not listed that can affect Combivir. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.