Abacavir and lamivudine

Name: Abacavir and lamivudine

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

Do not allow your medicine to run out completely before you get your prescription refilled. It is important that you not stop taking the medicine once you have started. If you miss several doses, you may have a dangerous or even fatal allergic reaction once you start taking this medication again.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What do I need to tell my doctor BEFORE I take Abacavir and Lamivudine?

For all patients taking abacavir and lamivudine:

  • If you have an allergy to abacavir, lamivudine, or any other part of this medicine.
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have any of these health problems: Kidney disease or liver disease.
  • If you are breast-feeding. Do not breast-feed while you take abacavir and lamivudine.


  • If your child weighs less than 55 pounds (25 kilograms).

This is not a list of all drugs or health problems that interact with this medicine.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take abacavir and lamivudine with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some other side effects of Abacavir and Lamivudine?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Dizziness.
  • Headache.
  • Not able to sleep.
  • Feeling tired or weak.
  • Upset stomach.
  • Loose stools (diarrhea).

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

Use Labeled Indications

HIV-1 infection: Treatment of HIV infection in combination with other antiretroviral agents

Dosing Pediatric

HIV-1 treatment: Children and Adolescents weighing ≥25 kg: Oral: One tablet (abacavir 600 mg and lamivudine 300 mg) once daily.

Pregnancy Considerations

The Health and Human Services (HHS) Perinatal HIV Guidelines consider abacavir in combination with lamivudine to be a preferred nucleoside reverse transcriptase inhibitor (NRTI) backbone for initial use in antiretroviral-naive pregnant women (do not use in women who are positive for the HLA-B*5701 allele). This backbone is not recommended with atazanavir/ritonavir or efavirenz if pretreatment HIV RNA is >100,000 copies/mL.

In general, women who become pregnant on a stable combination antiretroviral therapy (cART) regimen may continue that regimen if viral suppression is effective, appropriate drug exposure can be achieved, contraindications for use in pregnancy are not present, and the regimen is well tolerated (HHS [perinatal] 2016). See individual agents.

Usual Adult Dose for HIV Infection

1 tablet orally once a day

Use: In combination with other antiretroviral agents, for the treatment of HIV-1 infection

Abacavir / lamivudine Pregnancy Warnings

Animal studies with abacavir (high-dose) have revealed evidence of embryonic and fetal toxicity, including developmental toxicity, fetal anasarca, skeletal malformations, and increased incidence of stillbirth. Animal studies with lamivudine have failed to reveal evidence of teratogenicity; while early embryolethality was observed in rabbit studies (exposure levels similar to human levels), this effect was not seen in high-dose studies in rats. Placental transfer of each drug has been observed in humans. There are no controlled data in human pregnancy; however, based on observed outcomes with abacavir (more than 800 after first-trimester exposure and more than 1000 after second-/third-trimester exposure) and lamivudine (more than 1000 after first-trimester exposure and more than 1000 after second-/third-trimester exposure), the malformative risk is unlikely in humans. To monitor maternal-fetal outcomes of pregnant women exposed to antiretroviral therapy, an Antiretroviral Pregnancy Registry (APR) has been established. Healthcare providers are encouraged to prospectively register patients. For additional information: apregistry.com The APR has received prospective reports of over 2000 exposures to abacavir (over 900 exposed in the first trimester) and over 11,000 exposures to lamivudine (over 4300 exposed in the first trimester) resulting in live births; there was no difference between abacavir or lamivudine and overall birth defects compared with the background birth defect rate of 2.7% in the reference population. The prevalence of defects in the first trimester was 3% for abacavir and 3.1% for lamivudine. No increased risk of major birth defects observed for either drug compared to background rate. In 2 clinical trials, maternal, neonatal, and umbilical cord serum lamivudine levels were generally comparable. Amniotic fluid samples collected after natural rupture of membranes from a subset of patients confirmed placental transfer in humans. Amniotic fluid levels of lamivudine were usually 2 times greater than maternal serum levels, ranging from 1.2 to 2.5 mcg/mL (150 mg twice a day) and 2.1 to 5.2 mcg/mL (300 mg twice a day). AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans. US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus. AU TGA pregnancy category: B3 US FDA pregnancy category: Not assigned. Risk summary: Malformative risk with use of this drug in pregnant women is unlikely. Comments: A pregnancy exposure registry is available.