Generic Name: efavirenz (EF-a-VIR-enz)
Brand Name: Sustiva
Efavirenz is used for:
Treating HIV infection. It must be used in combination with other medicines. If efavirenz is taken alone to treat HIV, it may stop working.
Efavirenz is a nonnucleoside reverse transcriptase inhibitor (NNRTI). It works by blocking the growth of HIV.
Do NOT use efavirenz if:
- you are allergic to any ingredient in efavirenz, including if you have developed red, swollen, blistered, or peeling skin after taking any ingredient in efavirenz
- you have moderate to severe liver problems
- you are taking artemether-lumefantrine, bepridil, boceprevir, bortezomib, cabazitaxel, cisapride, an ergot medicine (eg, dihydroergotamine, ergotamine, methylergonovine), lurasidone, midazolam, pimozide, St. John's wort, ticagrelor, triazolam, or vandetanib
- you are taking another NNRTI (eg, nevirapine)
- you are taking another medicine that contains efavirenz, unless your doctor tells you otherwise
Contact your doctor or health care provider right away if any of these apply to you.
Before using efavirenz:
Some medical conditions may interact with efavirenz. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are able to become pregnant
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have high cholesterol, kidney problems, or a history of abnormal liver function tests or liver problems (eg, hepatitis)
- if you have a history of seizures, mental or mood problems (eg, depression), or suicidal thoughts or actions
- if you drink alcohol or have a history of alcohol or other substance abuse or dependence
Some MEDICINES MAY INTERACT with efavirenz. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Medicines that may harm the liver (eg, acetaminophen, isoniazid, ketoconazole, certain medicines for HIV infection, methotrexate) because the risk of liver side effects may be increased. Ask your doctor if you are unsure if any of your medicines might harm the liver
- Many prescription and nonprescription medicines (eg, used for anxiety, birth control, blood thinning, cancer, depression or other mental or mood problems, drug or other substance abuse or dependence, emergency contraception, heartburn, hepatitis C infection, high blood pressure, high cholesterol, HIV, hormone replacement, immune system suppression, infections, irregular heartbeat or other heart problems, malaria, migraine headaches, pain, seizures, sleep medicines, smoking cessation, Tourette syndrome), multivitamin products, and herbal or dietary supplements (eg, herbal teas, coenzyme Q10, garlic, ginseng, ginkgo, St. John's wort) because they may interact with efavirenz. Ask your doctor or pharmacist if you are unsure if any of your medicines might interact with efavirenz
This may not be a complete list of all interactions that may occur. Ask your health care provider if efavirenz may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use efavirenz:
Use efavirenz as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- An extra patient leaflet is available with efavirenz. Talk to your pharmacist if you have questions about this information.
- Take efavirenz by mouth on an empty stomach. Taking efavirenz with food, especially with a high-fat meal, may lead to increased blood levels of efavirenz. This may increase your risk of side effects.
- Take efavirenz with a full glass of water (8 oz [240 mL]).
- If you are taking the tablet doseform of the medicine, do not break it before swallowing.
- Do NOT take more than the recommended dose, change your dose, or stop taking efavirenz without checking with your doctor.
- Take efavirenz at the same time every day, preferably at bedtime unless otherwise directed by your doctor.
- Continue to use efavirenz even if you feel well. Do not miss any doses.
- If you miss a dose of efavirenz, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use efavirenz.
Important safety information:
- Efavirenz may cause drowsiness, dizziness, or trouble concentrating. These effects may be worse if you take it with alcohol or certain medicines. Use efavirenz with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
- Check with your doctor before you drink alcohol or use medicines that may cause drowsiness (eg, sleep aids, muscle relaxers) while you are using efavirenz; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
- Efavirenz may cause dizziness, drowsiness, trouble sleeping, trouble concentrating, or unusual dreams. These effects usually go away after you have taken efavirenz for about 2 to 4 weeks. Taking it at bedtime may help to decrease these effects. Check with your doctor if they continue or are severe.
- Keep a list of all the medicines that you take. Make a new list each time medicines are added or stopped. Find out about medicines that should not be taken while you are using efavirenz. Be sure that each of your health care providers knows all the medicines that you are taking.
- Efavirenz may improve immune system function. This may reveal hidden infections in some patients. Tell your doctor right away if you notice symptoms of infection (eg, fever, sore throat, weakness, cough, shortness of breath) after you start efavirenz.
- Changes in body fat (eg, an increased amount of fat in the upper back, neck, breast, and trunk, and loss of fat from the legs, arms, and face) may occur in some patients taking efavirenz. The cause and long-term effects of these changes are unknown. Discuss any concerns with your doctor.
- Efavirenz is not a cure for HIV infection. Patients may still get illnesses and infections associated with HIV. Remain under the care of your doctor.
- Efavirenz does not stop the spread of HIV to others through blood or sexual contact. Do not have any kind of sex without protection (eg, latex or polyurethane condoms) if you have HIV infection. Do not share needles, injection supplies, or items like toothbrushes or razors. Talk with your health care provider about ways to prevent the spread of HIV to others.
- When your medicine supply is low, get more from your doctor or pharmacist as soon as you can. Do not stop taking efavirenz, even for a short period of time. If you do, the virus may grow resistant to the medicine and become harder to treat.
- Efavirenz may interfere with certain lab tests, including cannabinoids/marijuana tests. Be sure your doctor and lab personnel know you are taking efavirenz.
- If you are able to become pregnant, you should have a pregnancy test before you begin taking efavirenz. Discuss any questions or concerns with your doctor.
- If you may become pregnant, you must use an effective form of birth control while you take efavirenz and for 12 weeks after you stop taking it. Hormonal birth control (eg, birth control pills) may not work as well while you are using efavirenz. You should always use a barrier form of birth control (eg, condoms), even if you already use a hormonal birth control method. If you have questions about effective birth control, talk with your doctor.
- Lab tests, including liver function and cholesterol and triglyceride levels, may be performed while you use efavirenz. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- Efavirenz should be used with extreme caution in CHILDREN younger than 3 years old; safety and effectiveness in these children have not been confirmed.
- The dose of efavirenz in CHILDREN is determined based on body weight; they will need to have regular weight checks while they take efavirenz.
- PREGNANCY and BREAST-FEEDING: Efavirenz may cause harm to the fetus. Do not become pregnant while you are taking it or for 12 weeks after you stop taking it. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using efavirenz while you are pregnant. It is not known if efavirenz is found in breast milk. Mothers infected with HIV should not breast-feed. There is a risk of passing the HIV infection or efavirenz to the baby.
Possible side effects of efavirenz:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Abnormal dreams; diarrhea; dizziness; drowsiness; headache; nausea; tiredness; trouble concentrating; trouble sleeping; upset stomach; vomiting.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); burning, numbness, or tingling; change in personality; confusion; cough; decreased coordination; delusions; fainting; fever, chills, or persistent sore throat; hallucinations; irregular heartbeat; memory loss; mental, mood, or behavior changes (eg, abnormal thoughts, agitation, aggression, anxiety, depression, nervousness, paranoia); mouth sores; rash with or without fever; red, swollen, blistered, or peeling skin; seizures; severe or persistent stomach pain; severe or persistent tiredness or weakness; shortness of breath; suicidal thoughts or behaviors; symptoms of liver problems (eg, dark urine, loss of appetite, pale stools, yellowing of the skin or eyes); vision changes.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include hallucinations; muscle twitching; severe dizziness, drowsiness, or coordination problems; trouble concentrating; trouble sleeping.Proper storage of efavirenz:
Store efavirenz at 77 degrees F (25 degrees C). Brief storage at temperatures between 59 and 86 degrees F (15 and 30 degrees C) is permitted. Store in a tightly closed container away from heat, moisture, and light. Do not store in the bathroom. Keep efavirenz out of the reach of children and away from pets.
- If you have any questions about efavirenz, please talk with your doctor, pharmacist, or other health care provider.
- Efavirenz is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take efavirenz or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about efavirenz. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to efavirenz. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using efavirenz.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.