Efavirenz is the preferred NNRTI recommended for first-line therapy in Australia.

While highly effective at controlling HIV, efavirenz is probably best known for it's psychotropic side-effect profile. When starting on efavirenz, people often feel strange or ill and experience vivid dreams. This is why it is not recommended for anyone with an existing psychiatic condition.

Basic info

Generic name efavirenz
Brand name Stocrin
Also known as Sustiva (US)
Drug class Non-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 600mg tablet; 200mg capsule; oral suspension 30mg per ml

Taking it

Like most anti-HIV drugs, efavirenz must be taken in combination with other drugs to be completely effective. Commonly, efavirenz 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 600mg tablet per day, usually at bedtime. Different doses are available for children.

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

efavirenz may be taken with or without food, but side effects may be increased if taken with or immediately after a meal

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 dizziness, drowsiness or insomnia, vivid dreams, confusion, abnormal thinking, impaired concentration.
  • Less common side effects may include aggravation of underlying psychiatric illness, depression, mania, rash.
  • Rare side effects may include headache, lipodystrophy, fever, dry mouth, alcohol intolerance, aches, pains and fatigue, fluid retention.
  • 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

Efavirenz can interact with other drugs or supplements that you are taking. These interactions can change the amount of each drug in your bloodstream and cause an under- or overdose. New interactions are being identified all the time. Drugs to watch out for include other ARVs, drugs to treat tuberculosis, for erectile dysfunction (such as Viagra), for heart rhythm (antiarrhythmics), or angina and for migraine headaches. Interactions are also possible with several antihistamines (allergy medications), sedatives, drugs to lower cholesterol or blood pressure, and anti-fungal drugs. Efavirenz decreases blood levels of methadone. Efavirenz can lower concentrations of buprenorphine. The herb St. John's Wort lowers the blood levels of some nonnucleoside reverse transcriptase inhibitors. Do not take it with efavirenz. The herbal remedy Ginkgo biloba should not be taken with efavirenz.