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Efavirenz Oral tablet

It is used with other medicines to treat HIV

Generic Name: efavirenz

Brand Names: Sustiva

What is this medicine?

EFAVIRENZ (e fa VEER ens) is an antiretroviral medicine. It is used with other medicines to treat HIV. This medicine is not a cure for HIV. It will not stop the spread of HIV to others.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • history of a drug or alcohol abuse problem
  • history of depression or other mental illness
  • liver disease
  • seizures
  • taking any other medicines
  • an unusual or allergic reaction to efavirenz, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take this medicine on an empty stomach, at least 30 minutes before or 2 hours after food. Do not take with food. Take your dose at bedtime. Take your medicine at regular intervals. Do not take your medicine more often than directed. For your anti-HIV therapy to work as well as possible, take each dose exactly as prescribed. Do not skip doses or stop your medicine even if you feel better. Skipping doses may make the HIV virus resistant to this medicine and other medicines. Do not stop taking except on your doctor's advice.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children as young as 3 years old for selected conditions, precautions do apply.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

Do not take this medicine with any of the following medications:
  • cerviastatin
  • cisapride
  • disopyramide
  • medicines for headaches like dihydroergotamine, ergonovine, ergotamine, methylergonovine
  • midazolam
  • pimozide
  • rifapentine
  • St. John's Wort
  • triazolam
  • voriconazole

This medicine may also interact with the following medications:

  • amiodarone
  • clarithromycin
  • female hormones, like estrogens or progestins and birth control pills, patches, rings, or injections
  • medicines for blood pressure like diltiazem, nifedipine, verapamil
  • medicines for cholesterol like simvastatin
  • medicines for depression, anxiety, or psychotic disturbances
  • medicines for fungal infections like ketoconazole, itraconazole, and posaconazole
  • medicines for seizures like carbamazepine, phenobarbital, phenytoin
  • medicines for sleep
  • methadone
  • other medicines for HIV
  • red yeast rice
  • rifabutin
  • rifampin
  • sirolimus
  • tacrolimus
  • warfarin

What should I watch for while using this medicine?

Visit your doctor or health care professional for regular check ups. Discuss any new symptoms with your doctor. You will need to have important blood work done while on this medicine.

HIV is spread to others through sexual or blood contact. Talk to your doctor about how to stop the spread of HIV.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Avoid alcohol and mood altering (street) drugs while taking this medicine because they can make these side effects worse.

Birth control pills may not work properly while you are taking this medicine. Talk to your doctor about using an extra method of birth control. Women who can still have children must use a reliable form of barrier contraception, like a condom or diaphragm.


Last Updated: November 30, 2009
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