An Overview of Trizivir (AZT/3TC/Abacavir)

Brand Name: Trizivir
Other Name(s): ABC/3TC/ZDV, abacavir sulfate/lamivudine/zidovudine
Drug Class: Nucleoside Reverse Transcriptase Inhibitors

Trizivir pill


Trizivir can cause serious, life-threatening side effects. These include allergic reactions, a buildup of lactic acid in the blood (lactic acidosis), liver problems, muscle weakness (myopathy), and blood disorders such as extremely reduced numbers of red blood cells (severe anemia) or reduced numbers of white blood cells (neutropenia).

Trizivir contains abacavir, an HIV medicine. People who take abacavir-containing products may have a serious allergic reaction (hypersensitivity reaction) that can cause death. Your risk of this allergic reaction is much higher if you have a gene variation called HLA-B*5701. Your health care provider can determine with a blood test if you have this gene variation. If you get a symptom from two or more of the following groups while taking Trizivir, contact your health care provider right away to find out if you should stop taking Trizivir.

  • Group 1 Symptoms: Fever
  • Group 2 Symptoms: Rash
  • Group 3 Symptoms: Nausea, vomiting, diarrhea, abdominal (stomach area) pain
  • Group 4 Symptoms: General ill feeling, extreme tiredness, or achiness
  • Group 5 Symptoms: Shortness of breath, cough, sore throat

Your pharmacist will give you a Medication Guide and Warning Card with a list of these symptoms. Carry this Warning Card with you at all times. If you stop Trizivir because of an allergic reaction, never take Trizivir or any other abacavir-containing medicine again. If you take Trizivir or any other abacavir-containing medicine again after you have had an allergic reaction, within hours you may get life-threatening symptoms that may include very low blood pressure or death. If you stop Trizivir for any other reason, even for a few days, and you are not allergic to Trizivir, talk with your health care provider before taking it again. Taking Trizivir again can cause a serious allergic or life-threatening reaction, even if you never had an allergic reaction to Trizivir before. If your health care provider tells you that you can take Trizivir again, start taking it when you are around medical help or people who can call a health care provider if you need one.

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

  • Weakness or tiredness
  • Unusual (not normal) muscle pain
  • Trouble breathing
  • Stomach pain with nausea and vomiting
  • Feeling cold, especially in your arms and legs
  • Dizziness or lightheadedness
  • Fast or irregular heartbeat

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

  • Yellowing of your skin or the whites of your eyes (jaundice)
  • Dark-colored urine
  • Light-colored bowel movements
  • Loss of appetite for several days or longer
  • Nausea
  • Pain, aching, or tenderness on your right side in the stomach area (abdominal pain)

Contact your health care provider right away if you have muscle weakness.

Trizivir can cause blood disorders such as extremely reduced numbers of red blood cells (severe anemia) or reduced numbers of white blood cells (neutropenia). Your doctor may follow your blood count closely while you are taking Trizivir.

If you have both HIV and hepatitis B virus (HBV) infection and take Trizivir, your HBV infection may get worse (flare up) if you stop taking Trizivir. But do not stop taking Trizivir without first talking to your health care provider. If your health care provider tells you to stop Trizivir, you will be monitored closely for several months to check your HBV infection, or you may receive a medicine to treat your HBV infection.

If you have HIV and HBV infection, the hepatitis B virus can change (mutate) during your treatment with Trizivir and become harder to treat (resistant).

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 also being treated for HCV infection with interferon alfa with or without ribavirin. If you are taking Trizivir as well as interferon with or without ribavirin and you experience side effects, tell your health care provider.

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

What Is Trizivir?

Trizivir is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection in adults, adolescents and children who weigh at least 88 pounds (40 kilograms). Trizivir can be used alone as a complete treatment regimen or with other HIV medicines.

Trizivir contains the following three different medicines combined in one pill:

  • Abacavir -- an HIV medicine called a nucleoside reverse transcriptase inhibitor (NRTI)
  • Lamivudine -- another HIV medicine (also an NRTI)
  • Zidovudine -- another HIV medicine (also an NRTI)

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, the three drugs in combination 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.

What Should I Tell My Health Care Provider Before Taking Trizivir?

Before taking Trizivir, tell your health care provider:

  • If you are allergic to any of the HIV medicines in Trizivir (abacavir, lamivudine, or zidovudine) or any other medicines.
  • If you have been tested and know whether or not you have a particular gene variation called HLA-B*5701.
  • If you have or have ever had liver problems, such as HBV or HCV infection.
  • If you have or have ever had kidney problems.
  • If you have low blood cell counts (a possible sign of bone marrow problems).
  • If you have or have ever had any blood disorders, such as anemia or neutropenia.
  • If you have or have ever had any muscle disorder, such as myopathy (muscle weakness).
  • If you have heart problems, smoke, or have diseases that increase your risk of heart disease, such as high blood pressure, high cholesterol, or diabetes.
  • If you drink alcohol or take medicines that contain alcohol.
  • If you are taking medicines containing abacavir, lamivudine, zidovudine, or emtricitabine.
  • If you have any other medical conditions.
  • If you are pregnant or plan to become pregnant. Whether Trizivir can harm an unborn baby is unknown. Trizivir should be used during pregnancy only if the potential benefits outweigh the risks. Talk to your health care provider about possible risks of taking Trizivir when pregnant.
  • If you are breastfeeding or plan to breastfeed. Do not breastfeed if you have HIV or are taking Trizivir.
  • If you are using hormone-based birth control (such as pills, implants, or vaginal rings). For more information about using birth control and HIV medicines at the same time, view the AIDSinfo HIV and Birth Control infographic.
  • About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Trizivir may affect the way other medicines or products work, and other medicines or products may affect how Trizivir works. Taking Trizivir together with certain medicines or products may cause serious, life-threatening side effects.

How Should I Take Trizivir?

Trizivir comes in tablet form. Each tablet contains:

  • 300 mg abacavir (brand name: Ziagen).
  • 150 mg lamivudine (brand name: Epivir).
  • 300 mg zidovudine (brand name: Retrovir).

Take Trizivir according to your health care provider's instructions.

Trizivir should be taken by mouth, with or without food.

If you take too much Trizivir, 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 Trizivir, 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 Trizivir, 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 Trizivir Cause?

Trizivir may cause side effects. Many side effects from HIV medicines, such as nausea or occasional dizziness, are manageable. See the AIDSinfo fact sheet on HIV Medicines and Side Effects for more information.

Other possible side effects of Trizivir include:

  • Changes in your immune system (called immune reconstitution inflammatory syndrome or IRIS). IRIS is 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.
  • Changes in body fat (including gain or loss of fat).
  • Increased risk of heart attack (myocardial infarction).

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 Trizivir. To learn more about possible side effects of Trizivir, read the drug label or package insert or talk to your health care provider or pharmacist.

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

How Should Trizivir Be Stored?

  • Store Trizivir at 59°F to 86°F (15°C to 30°C).
  • Do not use Trizivir if the original seal over the container opening is broken or missing.
  • Throw away Trizivir that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine.
  • Keep Trizivir and all medicines out of reach of children.

Where Can I Find More Information About Trizivir?

More information about Trizivir is available:

Manufacturer Information

ViiV Healthcare
Main number: 877-844-8872
Patient assistance (ViiV Connect): 844-588-3288

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

[Note from TheBody: This article was created by AIDSinfo, who last updated it on March 28, 2018. We have cross-posted it with their permission.]