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AIDSinfo Drug Database

AIDSinfo Drug Database

Drugs by class



Lamivudine  Audio icon

Brand Name: Epivir
Other Names: 3TC
Drug Class: Nucleoside Reverse Transcriptase Inhibitors
Approved Use: Treatment of HIV Infection
Drug Images:
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Epivir 150mg
Lamivudine gxEj7
Chemical Image:
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Molecular Weight: 229.2589


Lamivudine can cause serious, life-threatening side effects. These include lactic acidosis (buildup of lactic acid in the blood), severe liver problems, and pancreatitis (inflammation of the pancreas) in children at risk for pancreatitis.

Contact your health care provider right away if you have any of the following symptoms that could be signs of lactic acidosis:

  • Nausea.
  • Loss of appetite for several days or longer.
  • Excessive tiredness.
  • Weakness.
  • Unusual (not normal) muscle pain.
  • Trouble breathing.
  • Feel cold, especially in your arms and legs.
  • Feel dizzy or light-headed.
  • Fast or irregular heartbeat.
  • Dark-colored urine.
  • Light-colored stools (bowel movements).
  • Yellowing of your skin or the whites of your eyes (jaundice).
  • Pain, aching, or tenderness on the right side of your stomach area.
  • Stomach pain with nausea and vomiting.

Call your healthcare provider right away if your child develops signs and symptoms of pancreatitis including severe upper stomach-area pain, with or without nausea and vomiting. 

If you have both HIV and hepatitis B virus (HBV) infection and take lamivudine, your HBV infection may get much worse (flare up) if you stop taking lamivudine. Do not stop taking lamivudine without first talking to your health care provider. 

Epivir-HBV is a different type of lamivudine used to treat chronic HBV infection. You should not take Epivir-HBV if you have or may have HIV infection. Epivir-HBV does not contain an appropriate dose of lamivudine for treatment of HIV infection, and using Epivir-HBV could cause a person’s HIV to become less treatable with lamivudine and some other HIV medicines.

Worsening of liver disease (sometimes resulting in death) has occurred in people infected with both HIV and hepatitis C virus (HCV) who were taking HIV medicines and are also being treated for HCV infection with interferon with or without ribavirin. If you are taking lamivudine as well as interferon with or without ribavirin and you experience side effects, tell your health care provider.

While taking lamivudine, it is important to keep all of your appointments with your health care provider.

What is lamivudine?

Lamivudine is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection in adults and children 3 months of age and older. Lamivudine is always used in combination with other HIV medicines.

Lamivudine belongs to a class (group) of HIV drugs called nucleoside reverse transcriptase inhibitors (NRTIs). NRTIs block an HIV enzyme called reverse transcriptase. (An enzyme is a protein that starts or increases the speed of a chemical reaction.) By blocking reverse transcriptase, NRTIs prevent HIV from multiplying and can reduce the amount of HIV in the body.

HIV medicines can’t cure HIV/AIDS, but taking a combination of HIV medicines (called an HIV regimen) every day helps people with HIV live longer, healthier lives. HIV medicines also reduce the risk of HIV transmission. If you are taking HIV medicines, including lamivudine, don’t cut down on, skip, or stop taking them unless your health care provider tells you to.

Lamivudine is also effective against hepatitis B virus (HBV) and may be included in the HIV regimen of a person infected with both HIV and HBV. However, if you have both HIV and HBV infection and take lamivudine, your HBV infection may get much worse (flare up) if you stop taking lamivudine. Do not stop taking lamivudine without first talking to your health care provider. For more information on the HBV-related use of lamivudine, please refer to the HBV section of the Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents.

Epivir-HBV is a different type of lamivudine approved by FDA for the treatment of chronic HBV infection in adults and children 12 years of age and older. You should not take Epivir-HBV if you have or may have HIV infection. (See the WARNING above.)

What should I tell my health care provider before taking lamivudine?

Before taking lamivudine, tell your health care provider:

  • If you are allergic to lamivudine or any other medicines.
  • If you have or have had liver problems, including HBV or HCV infection.
  • If you have kidney disease.
  • If you have diabetes. Each 15-mL dose (150 mg) of lamivudine oral solution contains 3 grams of sucrose (common table sugar).
  • If you have or have had pancreatitis. (Lamivudine should be used with caution in children at risk for pancreatitis.)  
  • If you have any other medical conditions.
  • If you are pregnant or plan to become pregnant. Taking lamivudine during pregnancy has not been associated with an increased risk of birth defects. Talk to your health care provider about possible risks with taking lamivudine when pregnant.
  • If you are breastfeeding or plan to breastfeed. Do not breastfeed if you are infected with HIV or are taking lamivudine.
  • About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Lamivudine may affect the way other medicines or products work, and other medicines or products may affect how lamivudine works. Taking lamivudine together with certain medicines or products may cause serious and/or life-threatening side effects.

How should I take lamivudine?

Lamivudine (brand name: Epivir) comes in the following forms and strengths:

  • 150-mg tablets.
  • 300-mg tablets.
  • 10-mg/mL oral solution. An oral solution is a mixture of a medicine and a liquid that can be taken by mouth. 

Take lamivudine according to your health care provider’s instructions. For children 3 months and older, your healthcare provider will prescribe a dose of lamivudine based on your child’s body weight.

Take lamivudine by mouth, with or without food. Tell your healthcare provider if you have trouble swallowing tablets. Lamivudine also comes as a liquid (oral solution).

Always take lamivudine in combination with other HIV medicines.

If you take too much lamivudine, contact your health care provider or local poison control center (1-800-222-1222) right away, or go to the nearest hospital emergency room.

For more information on how to take lamivudine, see the FDA drug label from DailyMed. (DailyMed is a federal website that includes the most recent drug labels submitted to FDA.)

What should I do if I forget a dose?

If you miss a dose of lamivudine, take the missed dose as soon as you remember it. But if it is almost time for your next dose, skip the missed dose and just take your next dose at the regular time. Do not take two doses at the same time to make up for a missed dose.

What side effects can lamivudine cause?

Lamivudine can cause serious, life-threatening side effects. These include lactic acidosis (buildup of lactic acid in the blood), severe liver problems, and pancreatitis (inflammation of the pancreas) in children at risk for pancreatitis. (See the WARNING above.)

Other possible side effects of lamivudine include:

  • Changes in body fat (lipodystrophy).
  • Immune reconstitution inflammatory syndrome (IRIS), a condition that sometimes occurs when the immune system begins to recover after treatment with an HIV medicine. As the immune system gets stronger, it may have an increased response to a previously hidden infection. Tell your health care provider if you start having new symptoms after starting your HIV medicine.

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

These are not all the possible side effects of lamivudine. To learn more about possible side effects of lamivudine, read the drug label or package insert or talk to your health care provider or pharmacist.

The AIDSinfo fact sheet on HIV Medicines and Side Effects also includes information that may apply to lamivudine.

You can also report side effects to FDA at 1-800-FDA-1088 (1-800-332-1088) or online at

How should lamivudine be stored?

  • Store lamivudine tablets and oral solution at 68°F to 77°F (20°C to 25°C).
  • Do not use lamivudine if the original seal over the bottle opening is broken or missing.
  • Keep lamivudine oral solution in the container that it came in and keep the container tightly closed. 
  • Throw away lamivudine that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine.
  • Keep lamivudine and all medicines out of reach of children.

Where can I find more information about lamivudine?

More information about lamivudine is available:

Manufacturer Information

ViiV Healthcare

The above Patient Version drug summary is based on the following FDA label(s): Solution, tablet (film coated).

Last Reviewed: November 16, 2015

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