Abacavir

2 medicines

Abacavir is an antiretroviral used with other HIV medicines to lower the amount of virus in the blood. Before the first dose, you need a blood test for the HLA-B*5701 gene, since carriers can develop a severe, sometimes fatal hypersensitivity reaction and must never take it.

Triumeq

Abacavir, Dolutegravir, Lamivudine

600/50/300mg

Triumeq is a hiv medication containing Abacavir + Dolutegravir + Lamivudine, available as 600/50/300mg tablets.

from $8.69 / tablet View

Ziagen

Abacavir

300mg

Ziagen is a hiv medication containing Abacavir, available as 300mg tablets.

from $7.03 / tablet View

Key facts

  • Abacavir (an ingredient in the combination pill Triumeq) is a nucleoside reverse transcriptase inhibitor (NRTI). Combined with other antiretrovirals, it lowers HIV levels in the blood and protects the immune system.
  • You take it as part of a daily combination regimen; it does not cure HIV and needs to be continued for life.
  • Before you start, you need a blood test for the HLA-B*5701 gene. Carriers have a high risk of a severe, sometimes fatal hypersensitivity reaction and must not take abacavir.
  • If you get fever, rash, nausea, or unusual tiredness in the first six weeks, stop the drug and seek urgent care. Once a hypersensitivity reaction is confirmed or even suspected, never take abacavir again, since restarting it can trigger a rapid, life-threatening reaction even in someone who tolerated it before.

What abacavir treats

Abacavir treats HIV-1 infection in adults and children, always combined with at least two other antiretroviral drugs. It reduces the amount of virus circulating in the blood, known as the viral load, which slows damage to the immune system and lowers the risk of AIDS-related illness. It does not treat HIV-2 and does not clear the virus from the body.

How abacavir works

HIV copies its genetic material using an enzyme called reverse transcriptase. Abacavir mimics one of the building blocks this enzyme normally uses, and once the enzyme inserts it into the new viral strand, the chain cannot extend any further. This stops the virus completing its copying process and slows its spread to new cells.

Before you take it

  • Do not take abacavir if you have ever had a hypersensitivity reaction to it, or if your HLA-B*5701 test is positive.
  • Tell your doctor about liver disease; abacavir is processed by the liver, and moderate impairment may need a dose change, while severe impairment usually rules it out.
  • Heavy alcohol use can raise abacavir levels and add to liver strain.
  • Tell your prescriber about all other antiretrovirals and any herbal products, including St John's wort, which can lower antiretroviral levels.

Side effects

Common effects include nausea, headache, tiredness, and mild diarrhoea, which usually ease within the first weeks.

Stop and seek urgent medical care for any of these:

  • Rash together with fever, nausea, vomiting, or extreme tiredness in the first weeks of treatment, which can signal a hypersensitivity reaction.
  • Fever, chills, or flu-like symptoms appearing suddenly.
  • Unexplained shortness of breath or chest pain.
  • Yellowing skin or eyes, dark urine, or persistent abdominal pain, which can signal liver problems.

Safety essentials

  • HLA-B*5701 testing before the first dose is mandatory. Never start abacavir without it, and never restart abacavir after a hypersensitivity reaction, confirmed or suspected, even years later.
  • Carry a note or card recording that you take abacavir so emergency staff recognise hypersensitivity symptoms quickly if you become unwell.
  • Abacavir does not stop you passing HIV to others; keep using protection as advised by your care team.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.