Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) for HIV

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Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) for HIV


Generic NameBrand Name

Combination medicines

Generic NameBrand Name
efavirenz, emtricitabine, tenofovirAtripla

These medicines may be available in other combinations to treat HIV infection.

How It Works

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are antiretroviral medicines. They prevent the human immunodeficiency virus (HIV) from multiplying. When the amount of virus in the blood is kept at a minimum, the immune system has a chance to recover and grow stronger.

Why It Is Used

The use of three or more antiretroviral medicines (highly active antiretroviral therapy, or HAART) is the usual treatment for HIV infection.

The combination of medicines used for HAART will depend on your health, other conditions you might have (such as hepatitis), and results of testing. Talk to your doctor about the best treatment plan for you.

Treatment guidelines suggest the following for people with HIV:1, 2, 3, 4

  • Experts currently consider your CD4+ count and presence or absence of symptoms more important than your viral load, when considering treatment.
  • If your CD4+ cell count is below 500 cells per microlitre (mcL), treatment is recommended to help keep your immune system healthy and prevent AIDS.
  • If your CD4+ cell count is greater than 500, you may want to think about starting treatment.
  • If treatment is not started, your condition will be monitored with frequent CD4+ cell counts.
  • If you have symptoms of HIV or AIDS, doctors recommend starting treatment, whatever your CD4+ count is.
  • If you are pregnant, you should be treated to prevent your unborn baby (fetus) from becoming infected with HIV.
  • If you also have hepatitis B and are starting treatment for it, you should begin treatment for HIV also.

You may also want to start HIV treatment if your sex partner does not have HIV. Treatment of your HIV infection can help prevent the spread of HIV to your sex partner.3, 4

Experts recommend one of the following programs for people who begin treatment for HIV:1, 3

  • Efavirenz + tenofovir + emtricitabine
  • Ritonavir-boosted atazanavir + tenofovir + emtricitabine
  • Ritonavir-boosted darunavir + tenofovir + emtricitabine
  • Raltegravir + tenofovir + emtricitabine

Some of the medicines listed above may not be used in some provinces. For information on which medicines are used in your province, talk with your doctor.

Click here to view a Decision Point. HIV: When Should I Start Antiretroviral Medicines for HIV Infection?
Click here to view an Actionset. HIV: Taking Antiretroviral Drugs

How Well It Works

When compared with people who are given single- or double-medicine therapy, people who are given triple-medicine therapy (HAART):

  • Have a greater reduction in viral load.
  • Have better immune system recovery (measured by increased CD4+ cell counts).
  • Are less likely to develop resistance to their medicines.
  • Are likely to live longer.

Antiretroviral therapy can also decrease symptoms of HIV infection, such as fever, weakness, and weight loss.

The rate at which antiretrovirals decrease viral loads is affected by:1

  • CD4+ cell counts at the start of treatment.
  • Viral load at the start of treatment.
  • The dosage of the medicines.
  • Whether medicines are taken exactly as prescribed.
  • Whether antiretroviral medicines have been taken before.
  • Whether opportunistic infections are present.

Side Effects

Side effects of Non-nucleoside reverse transcriptase inhibitors can include:

  • Headache.
  • Nausea, vomiting, and diarrhea.
  • Rash.
  • Dizziness.
  • Vivid dreams and trouble sleeping.

In rare cases, nevirapine causes liver damage that can be severe and life-threatening. Regular blood tests may be needed to watch for liver problems.

Etravirine can cause a rare, but severe, skin reaction.

Side effects of any combination medicine can include the side effects of any of the single medicines in the combination.

Side effects usually are not as bad after your body has adjusted to the medicine. Report all side effects to your doctor. He or she may be able to help you reduce side effects by giving you other medicines.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

Resistance to single-medicine NNRTI treatment develops quickly. For this reason, they should be used only in combination with other antiretroviral medicines to treat HIV infection or to prevent or delay the development of resistance.

Efavirenz should not be taken at the same time as voriconazole (Vfend), a medicine that is used to treat serious fungal infections. Before you start a new medicine, talk to your doctor about all of the medicines you are taking.

Things to think about when choosing a combination of medicines include:

  • The ability of the medicines to reduce your viral load.
  • The likelihood that you will develop resistance to the medicines. If you have already been treated with a certain antiretroviral medicine, you may already know whether you are resistant to medicines in that class.
  • Side effects and your willingness to tolerate them.
  • The cost of treatment.

Many people think that antiretroviral medicines always have severe side effects. In fact, only a few people experience severe side effects.

Complete the new medication information form (PDF) (What is a PDF document?) to help you understand this medication.



  1. U.S. Department of Health and Human Services (2009). Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Available online:
  2. Hammer, Scott M, et al. (2008). Antiretroviral treatment of adult HIV infection: 2008 recommendations of the International AIDS Society USA Panel. JAMA, 300 (5): 555–570.
  3. British Columbia Centre for Excellence in HIV/AIDS (2011). Therapeutic guidelines—Antiretroviral treatment (ARV) of adult HIV infection. Available online:
  4. U.S. Department of Health and Human Services Panel on Antiretroviral Guidelines for Adults and Adolescents (2011). Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Available online:


By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Primary Medical Reviewer Brian D. O'Brien, MD - Internal Medicine
Specialist Medical Reviewer Peter Shalit, MD, PhD - Internal Medicine
Specialist Medical Reviewer Brian D. O'Brien, MD - Internal Medicine
Last Revised May 31, 2011

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.