Generic name: Efavirenz Tablets (e FAV e renz)
Brand name: Sustiva
Drug class: NNRTIs
Medically reviewed by Drugs.com. Last updated on Jan 23, 2021.
Uses of Efavirenz Tablets:
- It is used to treat HIV infection.
What do I need to tell my doctor BEFORE I take Efavirenz Tablets?
- If you are allergic to this medicine (efavirenz tablets); any part of this medicine (efavirenz tablets); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have had red, blistered, swollen, or peeling skin after taking efavirenz.
- If you have liver disease.
- If you take any drugs (prescription or OTC, natural products, vitamins) that must not be taken with this medicine (efavirenz tablets), like certain drugs that are used for hepatitis C, HIV, or infections. There are many drugs that must not be taken with this medicine (efavirenz tablets).
- If you are taking another drug that has the same drug in it.
- If you are breast-feeding. Do not breast-feed while you take this medicine (efavirenz tablets).
This is not a list of all drugs or health problems that interact with this medicine (efavirenz tablets).
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this medicine (efavirenz tablets) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take Efavirenz Tablets?
For all patients taking this medicine (efavirenz tablets):
- Tell all of your health care providers that you take this medicine (efavirenz tablets). This includes your doctors, nurses, pharmacists, and dentists.
- Avoid driving and doing other tasks or actions that call for you to be alert until you see how this medicine (efavirenz tablets) affects you.
- Do not run out of this medicine (efavirenz tablets).
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take this medicine (efavirenz tablets).
- Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
- This medicine is not a cure for HIV. Stay under the care of your doctor.
- This medicine does not stop the spread of diseases like HIV or hepatitis that are passed through blood or having sex. Do not have any kind of sex without using a latex or polyurethane condom. Do not share needles or other things like toothbrushes or razors.
- This medicine may raise the chance of seizures in some people, including people who have had seizures in the past. Talk to your doctor to see if you have a greater chance of seizures while taking this medicine (efavirenz tablets).
- This medicine may cause high cholesterol and triglyceride levels. Talk with the doctor.
- A type of abnormal heartbeat (prolonged QT interval) can happen with this medicine (efavirenz tablets). Call your doctor right away if you have a fast heartbeat, a heartbeat that does not feel normal, or if you pass out.
- Changes in your immune system can happen when you start taking drugs to treat HIV. If you have an infection that you did not know you had, it may show up when you take this medicine (efavirenz tablets). Tell your doctor right away if you have any new signs after you start this medicine (efavirenz tablets), even after taking it for several months. This includes signs of infection like fever, sore throat, weakness, cough, or shortness of breath.
- Liver problems have happened with this medicine (efavirenz tablets). Sometimes these problems have been severe, leading to liver transplant or death. Liver problems may happen in people with or without liver disease. Talk with the doctor.
- Birth control pills and other hormone-based birth control may not work as well to prevent pregnancy. Use some other kind of birth control also like a condom when taking this medicine (efavirenz tablets).
- This medicine may cause harm to an unborn baby. A pregnancy test will be done before you start this medicine (efavirenz tablets) to show that you are NOT pregnant.
- Women must use birth control while taking this medicine (efavirenz tablets) and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
- If your child's weight changes, talk with the doctor. The dose of this medicine (efavirenz tablets) may need to be changed.
How is this medicine (Efavirenz Tablets) best taken?
Use this medicine (efavirenz tablets) as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take this medicine (efavirenz tablets) at bedtime.
- Take on an empty stomach.
- Take with a full glass of water.
- Swallow whole. Do not chew or crush.
- Do not split or break tablet.
- If you have trouble swallowing, talk with your doctor.
- This medicine interacts with many other drugs. The chance of this medicine (efavirenz tablets)'s side effects may be raised or how well this medicine (efavirenz tablets) works may be lowered. The chance of the other drugs' side effects may also be raised. This may include very bad, life-threatening, or deadly side effects. Check with your doctor and pharmacist to make sure that it is safe for you to take this medicine (efavirenz tablets) with all of your other drugs (prescription or OTC, natural products, vitamins).
- It is important that you do not miss or skip a dose of this medicine (efavirenz tablets) during treatment.
- Keep taking this medicine (efavirenz tablets) as you have been told by your doctor or other health care provider, even if you feel well.
What do I do if I miss a dose?
- Take a missed dose as soon as you think about it.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
- If you are not sure what to do if you miss a dose, call your doctor.
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- New or worse behavior or mood changes like depression or thoughts of suicide.
- Change in body fat.
- Memory problems or loss.
- Very bad dizziness or passing out.
- Severe nervous system problems have happened. These may include feeling confused, behavior or mood changes, balance problems, other movement problems, or hallucinations (seeing or hearing things that are not there). Sometimes, this has happened months to years after starting this medicine (efavirenz tablets). Call your doctor right away if you have any of these effects.
- A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
What are some other side effects of Efavirenz Tablets?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Upset stomach or throwing up.
- Feeling tired or weak.
- Nervous system problems are common with this medicine (efavirenz tablets). These may include dizziness, sleepiness, trouble sleeping or focusing, or abnormal dreams. Most of the time, this goes away after 2 to 4 weeks. Taking this medicine (efavirenz tablets) at bedtime may help with these effects. If you feel dizzy, sleepy, or have trouble focusing, avoid driving and doing other tasks or actions that call for you to be alert. Call your doctor if these effects last, they bother you, or are severe.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
If OVERDOSE is suspected:
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
How do I store and/or throw out Efavirenz Tablets?
- Store at room temperature in a dry place. Do not store in a bathroom.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
Consumer information use
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else's drugs.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this medicine (efavirenz tablets), please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
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More about efavirenz
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Drug Images
- Drug Interactions
- Pricing & Coupons
- En Español
- 8 Reviews
- Drug class: NNRTIs
- Other brands
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