Last update: November 2006
Epivir – brand name
3TC – commonly-used name
lamivudine – generic name
Epivir belongs to a class of HIV drugs called nucleoside reverse transcriptase inhibitors (NRTIs), also known as nucleoside analogs or “nukes.”
Epivir and the other NRTIs block reverse transcriptase, a protein that HIV needs to make more copies of itself. This may slow down HIV disease.
The Food and Drug Administration (FDA) has approved Epivir for use in combination with other HIV drugs for the treatment of HIV infection in adults and children more than three months old.
The FDA also granted tentative approval of generic formulations of Epivir. These versions are not yet available in the U.S.
Epivir comes in:
- 150 milligram (mg) tablets
- 300 mg tablets
- Liquid form
The usual dose for adults is 300 mg, taken as either:
- One 150 mg tablet twice daily
- One 300 mg tablet once daily
If you have a kidney problem, your dose of Epivir may need to be lowered.
Check with your child’s doctor for children’s dosing.
Epivir must be used with other HIV medications to treat HIV.
You can take Epivir with food or on an empty stomach, but taking it with food may cut down on nausea or other side effects.
Many people use Epivir in combination pills that also contain other NRTI drugs:
- Combivir: Epivir plus Retrovir (zidovudine or AZT)
- Epzicom: Epivir plus Ziagen (abacavir)
- Trizivir: Epivir plus Retrovir plus Ziagen (abacavir)
As with all HIV drugs, it is important to take Epivir as prescribed. Missing or skipping doses can cause your blood levels of the drug to fall too low and resistance can develop. When your virus becomes resistant to an HIV medication, that drug may stop working.
Epivir can be used if you are beginning treatment for the first time.
Epivir can be used if you have developed resistance to another NRTI.
Epivir probably will not work as well if your HIV is already resistant to certain drugs, such as Emtriva (emtricitabine or FTC).
Your doctor can run a resistance test to help determine whether Epivir is likely to work for you.
If your virus develops resistance to Epivir then it may stop working or not work as well for you. You also may not get as much benefit from some of the other NRTIs. However, Retrovir may work better if you have Epivir-resistant virus.
Even if your virus develops resistance to Epivir, you may still get some benefit from drug combinations that include Epivir.
Sometimes taking more than one medication can cause drug interactions. Taking certain drugs with Epivir can change the amount of each drug in your blood. Your doctor may need to adjust the doses of your drugs to avoid under- or overdosing.
Use caution if you are taking interferon to treat hepatitis C. There have been some reports of liver failure in people taking interferon at the same time as Epivir. If you are taking these drugs together, your doctor should monitor you for treatment-related side effects, especially liver problems and blood problems such as anemia and neutropenia.
Several other medications can make the side effects of Epivir worse. Be sure your doctor knows about all the medications you are taking (including over-the-counter, prescription, street drugs, and herbs), even if you only use them occasionally.
For more information and additional resources to check interactions between the particular drugs you are taking, see our info sheet on drug interactions.
Epivir is generally very well tolerated. If you do experience any side effects from Epivir, they are likely to be temporary and go away as your body adjusts to the medication. If you experience any of the side effects listed below, call your doctor for advice. Do not just stop taking your medication.
- Fatigue (unusual tiredness)
- Neuropathy (pain or numbness in the feet and hands)
More serious side effects:
- Low white blood cell count (neutropenia) or low red blood cell count (anemia).
- An increase of lactic acid in the blood ( lactic acidosis), an enlarged and fatty liver, and liver failure have been reported in people using NRTIs. Lactic acidosis is a rare but potentially fatal side effect. Symptoms include nausea, vomiting, or stomach pain; feeling very weak and tired; shortness of breath.
- Lipodystrophy, which may include elevated blood sugar (glucose), elevated lipid levels ( cholesterol and triglycerides), and fat gain or loss in certain areas. The exact causes of lipodystrophy are not known, but may include HIV and/or HIV drugs. It is unclear if Epivir will cause or impact symptoms of lipodystrophy. For more information on lipodystrophy, see our info sheet.
If you are experiencing persistent, unusual, or serious side effects, call your doctor right away.
Epivir has been studied in both men and women. Its effectiveness and side effects seem very similar in both men and women. But some research suggests that women are more likely than men to develop liver problems and the rare but very serious side effect, lactic acidosis, while taking NRTI drugs.
- The CAESAR study, published in 1997, included 1,840 participants; 242
(about 13 percent) were women. The study showed that people who added Epivir to
their current regimen of Retrovir, Retrovir plus Videx, or Retrovir plus Hivid
CD4 cell increases and were half as likely to experience HIV disease
- Several other studies showed that adding Epivir to Retrovir reduced viral load and increased CD4 cell counts. One of these studies, NUCA3002, included 42 women out of a total of 254 participants (about 17 percent).
- Epivir has also been studied in pregnant women. In one study, 445 HIV+ women who took Epivir along with Retrovir during pregnancy were compared with 899 women who took Retrovir alone. The women who took both drugs (and whose babies received both Epivir and Retrovir for six weeks after birth) were less likely to transmit HIV to their babies than the women who took only Retrovir.
Studies have shown that pregnant women who use Epivir in combination with Retrovir can greatly reduce the risk of passing HIV on to their babies. Epivir has been used during pregnancy without any significant negative effect to mother or baby; however, long- term effects on the child are not known.
Check with your doctor about the best treatment options for you and your baby if you are thinking of getting pregnant.
Click this link for more information about pregnancy.
A lower dose formulation of Epivir, called Epivir-HBV, is used to treat hepatitis B infection. Epivir-HBV is for people who have hepatitis B only; it should not be used by people who have both hepatitis B and HIV.
Get tested for hepatitis B before you start taking Epivir to treat HIV. If you are co-infected with both viruses, speak to your doctor about treatment options.
In addition, if you are co-infected and taking Epivir for HIV treatment, discontinuing the drug may result in worsening hepatitis symptoms.
People who are starting HIV treatment for the first time may develop Immune Reconstitution Syndrome or IRS (also called Immune Reconstitution Inflammatory Syndrome or IRIS). IRS can happen as a result of the immune system getting stronger and responding to an HIV-related infection such as Mycobacterium avium infection (MAC), cytomegalovirus (CMV), Pneumocystis jirovecii pneumonia (PCP), or tuberculosis (TB). People may have been treated for these infections in the past or not even know they have them. If you notice any unusual symptoms soon after starting HIV drugs for the first time, let your doctor know right away so you can be evaluated and, if necessary, treated.