Drug Database: Efavirenz

What is efavirenz?What is efavirenz?

What is efavirenz?

Efavirenz is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection in adults and in children. Efavirenz is always used in combination with other HIV medicines.

For more information on the use of efavirenz in people with HIV, please refer to the Guidelines for the Use of Antiretroviral Agents in Adults and Adolescents with HIV and the Guidelines for the Use of Antiretroviral Agents in Pediatric HIV Infection.

HIV medicines cannot cure HIV/AIDS, but taking HIV medicines every day helps people with HIV live longer, healthier lives. HIV medicines also reduce the risk of HIV transmission. If you are taking HIV medicines, do not cut down on, skip, or stop taking them unless your health care provider tells you to.

What should I tell my health care provider before taking efavirenz?What should I tell my health care provider before taking efavirenz?

What should I tell my health care provider before taking efavirenz?

Before taking efavirenz, tell your health care provider:

• If you are allergic to efavirenz or any other medicines.
• If you have a heart condition.
• If you have ever had a mental health problem.
• If you have ever used street drugs or large amounts of alcohol.
• If you have liver problems, including hepatitis B virus infection (HBV) or hepatitis C virus infection (HCV).
• If you have ever had a seizure or if you take a medicine to help prevent seizures.
• If you have any other medical conditions.
• If you are pregnant or plan to become pregnant. Talk to your health care provider about the risks and benefits of taking efavirenz during pregnancy. For more information on the use of efavirenz during pregnancy, please refer to the Recommendations for the Use of Antiretroviral Drugs During Pregnancy and Interventions to Reduce Perinatal HIV Transmission in the United States.
• If you are breast/chestfeeding or plan to breast/chestfeed. For people with HIV in the United States, the Guideline recommends speaking with your health care provider to discuss options for feeding your baby. People with suppressed viral load have a less than 1% chance of transmitting HIV to their baby via their own milk.
• If you are using hormone-based birth control (such as injections, vaginal rings, implants, a contraceptive patch, or birth control pills). Efavirenz may make these forms of birth control less effective. Your health care provider can help you decide how to adjust your birth control while you are taking efavirenz. For more information about using birth control and HIV medicines at the same time, view the HIVinfo HIV and Birth Control infographic.
• About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Efavirenz may affect the way other medicines or products work, and other medicines or products may affect how efavirenz works. Taking efavirenz together with certain medicines or products may cause serious side effects.

How should I take efavirenz?How should I take efavirenz?

How should I take efavirenz?

Efavirenz comes in the following forms and strengths:

• 50-mg, 100-mg, and 200-mg capsules
• 600-mg tablets

Take efavirenz according to your health care provider’s instructions. Do not miss a dose of efavirenz, and do not change your dose or stop taking efavirenz without first talking with your health care provider.

Take efavirenz on an empty stomach, preferably at bedtime. Taking efavirenz at bedtime might help to make some of the side effects less bothersome. Do not break efavirenz tablets. Swallow efavirenz tablets and capsules whole with liquid.

Tell your health care provider if you or your child have trouble swallowing tablets or capsules. Your health care provider may recommend that you open the efavirenz capsule and mix the contents with a small amount of food or infant formula. See the "Instructions for Use" that come with efavirenz capsules for complete instructions on the capsule sprinkle method. Adults and children who take efavirenz using the capsule sprinkle method should not eat for 2 hours after taking a dose of efavirenz.

Always take efavirenz in combination with other HIV medicines.

If you have taken too much efavirenz, contact your health care provider or local poison control center (1-800-222-1222 or online) right away, or go to the nearest hospital emergency room.

For more information on how to take efavirenz, see the FDA drug labels for efavirenz capsule and efavirenz tablet (film coated).

What should I do if I forget a dose?What should I do if I forget a dose?

What should I do if I forget a dose?

If you miss a dose of efavirenz, take the missed dose as soon as you remember it. But if it is almost time for your next dose, skip the missed dose and just take your next dose at the regular time. Do not take two doses at the same time to make up for a missed dose.

What side effects can efavirenz cause?What side effects can efavirenz cause?

What side effects can efavirenz cause?

Efavirenz may cause side effects. Some side effects of efavirenz can be serious as noted above. Many side effects from HIV medicines, such as nausea or occasional dizziness, are manageable. See the HIVinfo fact sheet on HIV Medicines and Side Effects for more information.

Other possible side effects of efavirenz include:

• Nervous system symptoms, including dizziness, trouble sleeping, unusual dreams, trouble concentrating, drowsiness, and lack of coordination or difficulty with balance. These symptoms may become worse if you drink alcohol, take certain medicines for mental health problems, or use certain street drugs during treatment with efavirenz.
• Seizures, which are more likely to happen if you have had seizures in the past.
• Changes in your immune system (called immune reconstitution inflammatory syndrome or IRIS). IRIS is a condition that sometimes occurs when the immune system begins to recover after treatment with an HIV medicine. As the immune system gets stronger, it may have an increased response to a previously hidden infection.
• Changes in body fat (lipodystrophy syndrome).
• Increases in the levels of certain fats (cholesterol and triglycerides) in the blood (hyperlipidemia).

Tell your health care provider if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of efavirenz. To learn more about possible side effects of efavirenz, read the drug labels or package inserts for efavirenz capsule and efavirenz tablet (film coated) or talk to your health care provider or pharmacist.

You can report side effects to FDA at 1-800-FDA-1088 (1-800-332-1088) or online.

How should efavirenz be stored?How should efavirenz be stored?

How should efavirenz be stored?

• Store efavirenz capsule and tablets at room temperature, 68°F to 77°F (20°C to 25°C).
• Keep efavirenz in the container that it came in and keep the container tightly closed.
• Do not use efavirenz if the original seal over the container opening is broken or missing.
• Throw away efavirenz that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine.
• Keep efavirenz and all medicines out of reach of children.

Where can I find more information about efavirenz?Where can I find more information about efavirenz?

Where can I find more information about efavirenz?

• For more information on the use of efavirenz in people with HIV, please refer to the Guidelines for the Use of Antiretroviral Agents in Adults and Adolescents with HIV and the Guidelines for the Use of Antiretroviral Agents in Pediatric HIV Infection.
• This Patient Version drug summary is based on the following FDA label(s): Capsule; Tablet (film coated). The Patient Information section and Instructions For Use include information for people taking efavirenz.
• The American Hospital Formulary Service (AHFS) Patient Medication Information for efavirenz available from MedlinePlus.
• Efavirenz-related research studies, from ClinicalTrials.gov. (The ClinicalTrials.gov search can be modified so that you can get results that better match your interests.)
• A list of FDA-approved HIV medicines, from HIVinfo.