Efavirenz

1 medicine

Efavirenz is an antiretroviral used with other HIV medicines to control the virus. It is taken at bedtime because of common central nervous system and psychiatric effects, and strict daily adherence is essential to prevent drug resistance.

Sustiva

Efavirenz

200/600mg

Sustiva is a hiv medication containing Efavirenz, available as 200/600mg tablets.

from $3.87 / tablet View

Key facts

  • Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) used as part of combination antiretroviral therapy (ART) for HIV; it is never taken alone.
  • Take it at bedtime on an empty stomach: this reduces dizziness, vivid dreams and other central nervous system effects, which are usually worst in the first weeks.
  • It can cause psychiatric effects, including depression, anxiety, and rarely suicidal thoughts; tell your prescriber straight away about any mood change.
  • Missing doses lets HIV levels rebound and encourages drug resistance. Take it every day, at the same time, exactly as prescribed.

What efavirenz treats

Efavirenz treats HIV-1 infection in adults and children, always combined with at least two other antiretroviral drugs. Together, these lower the amount of virus in the blood (viral load), protect immune function, and reduce the risk of HIV-related illness. It does not cure HIV and does not work if taken alone or inconsistently.

How efavirenz works

HIV needs an enzyme called reverse transcriptase to convert its genetic material (RNA) into DNA before it can insert itself into your cells. Efavirenz binds to and blocks this enzyme, stopping that step. Combined with drugs that block the virus at other stages, this keeps the amount of virus in the blood suppressed.

Before you take it

  • Tell your prescriber about liver disease, since efavirenz is broken down by the liver and levels can build up.
  • Tell your prescriber about any history of depression, anxiety, or other mental health conditions, so mood can be monitored during treatment.
  • Avoid taking it with a high-fat meal, which increases absorption and can worsen side effects.
  • St John's wort, rifampicin, some anti-seizure medicines, and hormonal contraceptives can all interact with efavirenz; check every new medicine with your pharmacist, since efavirenz can also make hormonal contraception less reliable.

Side effects

Common effects, especially in the first weeks, include dizziness, vivid or unusual dreams, trouble sleeping, headache, and mild rash.

Stop and seek urgent medical care for any of these:

  • Severe rash or blistering skin (possible Stevens-Johnson syndrome).
  • New or worsening depression, anxiety, hallucinations, or thoughts of self-harm.
  • Yellowing of the skin or eyes.
  • Swelling of the face, lips or tongue, or difficulty breathing.

Safety essentials

  • Central nervous system and psychiatric effects are common: take efavirenz at bedtime, avoid driving until you know how it affects you, and report new depression, anxiety, or suicidal thoughts immediately.
  • Efavirenz is always one part of combination HIV therapy; taking it alone or skipping doses allows the virus to develop resistance, which can limit future treatment options.
  • Regular viral load, CD4 count, and liver function tests guide how well treatment is working.

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