Lamivudine is an antiviral medication that prevents human immunodeficiency virus (HIV) or hepatitis B virus cells from multiplying in your body.

Epivir is for treating HIV, which causes the acquired immunodeficiency syndrome (AIDS). Epivir is not a cure for HIV or AIDS.

Epivir-HBV is for treating hepatitis B. Epivir-HBV should not be used in people who are infected with both hepatitis B and HIV.

Lamivudine may also be used for purposes not listed in this medication guide.

You should not take lamivudine if you are allergic to it.

The Epivir brand of lamivudine (for treating HIV) should not be taken together with any HIV combination medicine that contains lamivudine or emtricitabine. This includes Atripla, Combivir, Complera, Emtriva, Epzicom, Trizivir, and Truvada.

The Epivir-HBV brand of lamivudine (for treating hepatitis B) should not be taken together with any other medication that contains lamivudine, which includes Combivir, Epivir, Epzicom, and Trizivir.

Before taking lamivudine, tell your doctor if you have kidney disease, liver disease, a history of pancreatitis, or if you have used a medicine similar to lamivudine in the past, such as abacavir (Ziagen), didanosine (Videx), emtricitabine (Atripla, Complera, Emtriva, Truvada), stavudine (Zerit), tenofovir (Viread), zalcitabine (Hivid), or zidovudine (Retrovir).

Some people develop lactic acidosis while taking lamivudine. Early symptoms may get worse over time and this condition can be fatal. Get emergency medical help if you have even mild symptoms such as: muscle pain or weakness, numb or cold feeling in your arms and legs, trouble breathing, stomach pain, nausea with vomiting, fast or uneven heart rate, dizziness, or feeling very weak or tired.

If you have hepatitis B you may develop liver symptoms after you stop taking this medication, even months after stopping. Your doctor may want to check your liver function for several months after you stop using lamivudine. Visit your doctor regularly.

Lamivudine can also cause severe or life-threatening effects on your liver or pancreas. Call your doctor at once if you have any of these symptoms while taking lamivudine: severe pain in your upper stomach spreading to your back, nausea and vomiting, fast heart rate, itching, loss of appetite, dark urine, clay-colored stools, or jaundice (yellowing of the skin or eyes).

Epivir tablets and liquid contain a higher dose of lamivudine than Epivir-HBV. Each time you get a refill of this medication, be sure you have received the correct brand to treat your condition.

You should not take lamivudine if you are allergic to it.

The Epivir brand of lamivudine (for treating HIV) should not be taken together with any HIV combination medicine that contains lamivudine or emtricitabine. This includes:

• Atripla (efavirenz, emtricitabine, and tenofovir);

• Combivir (lamivudine and zidovudine);

• Complera (rilpivirine, emtricitabine, and tenofovir);

• Emtriva (emtricitabine);

• Epzicom (abacavir and lamivudine);

• Trizivir (abacavir, lamivudine, and zidovudine); and

• Truvada (emtricitabine and tenofovir).

The Epivir-HBV brand of lamivudine (for treating hepatitis B) should not be taken together with any other medication that contains lamivudine, which includes:

• Combivir (lamivudine and zidovudine);

• Epivir (lamivudine) for treating HIV;

• Epzicom (abacavir and lamivudine); and

• Trizivir (abacavir, lamivudine, and zidovudine).

To make sure you can safely take lamivudine, tell your doctor if you have any of these other conditions:

• liver disease (especially hepatitis B if you also have HIV);

• kidney disease;

• a history of pancreatitis; or

• if you have used a medicine similar to lamivudine in the past, such as abacavir (Ziagen), didanosine (Videx), emtricitabine (Atripla, Complera, Emtriva, Truvada), stavudine (Zerit), tenofovir (Viread), zalcitabine (Hivid), or zidovudine (Retrovir).

Some people develop a life-threatening condition called lactic acidosis while taking lamivudine. You may be more likely to develop lactic acidosis if you are overweight or have liver disease, if you are a woman, or if you have taken HIV or AIDS medications for a long time. Talk with your doctor about your individual risk.

FDA pregnancy category C. It is not known whether lamivudine will harm an unborn baby. HIV can be passed to your baby if you are not properly treated during pregnancy. Tell your doctor if you are pregnant or plan to become pregnant during treatment. Take all of your HIV medicines as directed to control your infection.

Lamivudine can pass into breast milk and may harm a nursing baby. You should not breast-feed while you are using lamivudine to treat hepatitis B. Women with HIV or AIDS should not breast feed a baby. Even if your baby is born without HIV, the virus may be passed to the baby in your breast milk.

If you are pregnant, your name may be listed on a pregnancy registry. This is to track the outcome of the pregnancy and to evaluate any effects of lamivudine on the baby.

If you have diabetes, you should know that the liquid forms of lamivudine contain 3 to 4 grams of sucrose (sugar) per dose.