- Efavirenz (tradenames Sustiva or Stocrin in some other European countries) is a non-nucleoside reverse transcriptase inhibitor (NNRTI).
- Generic formulations of efavirenz may be used in the UK and these will have a different brand name, a different pill size and shape and different packaging. The active ingredients will be just as effective as the original formulation.
- Standard adult doses might depend on formulations available in your country.
1 x 600 mg tablet, once-daily. This was the original dose.
1 x 400 mg tablet, once-daily. Several recent studies showed that a lower 400 mg can be just as effective, with slightly fewer side effects. The lower dose is recommended in WHO guidelines.
- Take before bedtime, on an empty stomach (or not with a high fat meal). A high fat meal increases drug levels of efavirenz by 60%. This increases the likelihood of side effects.
- Side effects: sleep disturbance (including nightmares), mood changes (including anxiety and depression), rash, liver toxicity, lipid changes, kidney problems. Taking at night can help reduce side effects as you will be sleeping when drug levels are highest. A high fat meal can increase drug levels but other food is okay.
- Other notes: can now be taken during pregnancy or by women trying for a baby. Originally alternative meds were recommended.
- Efavirenz is widely used with either Truvada or Kivexa in first-line combinations.
- Efavirenz is included with tenofovir and FTC in the fixed dose combination Atripla.
Information on efavirenz side effects from the i-Base side effects guide.
The European patient information and detailed Product Information for efavirenz (Sustiva) from this link at the European Medicines Agency (EMA) website. Documents for different generic versions are also available online.
The Patient Information is a simplified summary: what the drug is, why it is used, results from studies and cautions including side effects.
The Product Information is a detailed technical summary that you can access as a PDF file by clicking the ‘Product Information’ tab. It describes more precisely how the drug works and how it is processed by your body. This includes, for example, reported food interaction studies in terms of calories or fat content. It includes more details of the study results and a full list of side effects and drug interactions.