Abacavir is an NRTI which is highly potent in people who have not taken antiretrovial therapy and is also often effective in people who have taken HIV treatments before.

A main concern with any regimen containing abacavir is the possibility of developing a severe hypersensitivity reaction to the drug. It is also not recommended for people already at risk of heart attack.

However, abacavir is one of the antiretrovirals that can cross the blood-brain barrier and combat HIV in the central nervous system and reduce viral load in the cerebrospinal fluid.

Basic info

Generic name abacavir
Brand name Ziagen
Also known as
Drug class Nucleoside/Nucleotide Reverse Transcriptase Inhibitors
Pediatric dosing? Available in doses suitable for children and/or young people.
Availability in Australia Available on the Pharmaceutical Benefits Scheme (PBS) through S100 prescribers since
This drug may be available through clinical trials in Australia.
You may be able to import this drug from overseas for your personal use.
Formulation 300mg tablet;20mg per mL, 240mL oral solution

Taking it

Like most anti-HIV drugs, abacavir must be taken in combination with other drugs to be completely effective. Commonly, abacavir is combined with one other nucleoside (NRTI) drug and either a protease inhibitor or non-nucleoside, although other combinations are sometimes used. Your doctor will advise you on the right combination of drugs to suit your circumstances.


The normal adult dose is one 300mg tablet twice a day or two 300mg tablets once a day. For children and adolescents aged three months to 16 years, the recommended dosage is 8mg/kg twice a day (up to a maximum of 300mg twice a day).

Regardless of what you read on this website or elsewhere, you should always take your medications according to your doctor's instructions. If you're unsure, speak to your doctor or pharmacist.

With or without food

abacavir may be taken with or without food

Side effect

All drugs can produce side effects in some people. These may be mild, moderate or severe, so you should be aware of potential side effects before starting any drug, and speak to your doctor if you experience side effects that concern you.

  • Common side effects may include nausea (upset stomach, feeling sick to the stomach), diarrhoea, vomiting, headache, fatigue, lethargy, fever, loss of appetite.
  • Rare side effects may include serious hypersensitivity reaction which may be life-threatening, lactic acidosis with hepatic steatosis.
  • It's unlikely you will experience all of these side effects, and you may not experience any side effects at all. Before starting any new drug, ask your doctor about side effects you might experience and discuss strategies for dealing with side effects if they do occur. If you experience any significant side effect you should continue taking your medicine and see your doctor as soon as possible.

Interactions with other drugs

Patients taking abacavir and methadone hydrochloride should be monitored for methadone withdrawal symptoms as the drug increases clearance of methadone from the body. Alcohol increases the blood levels of abacavir. This is more likely to be a problem for people with liver disease and it is not recommended that they take abacavir.