Efavirenz (By mouth)

Introduction

Efavirenz (ef-a-VYE-renz)

Used with other medicines to treat human immunodeficiency virus (HIV) infection. HIV causes acquired immune deficiency syndrome (AIDS). Efavirenz does not cure HIV or AIDS, but it may slow the worsening of the disease.

Brand Name(s)

Sustiva

There may be other brand names for this medicine.

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to efavirenz, or if you are pregnant. You should not use this medicine if you are also using astemizole (Hismanal®), bepridil (Vascor®), cisapride (Propulsid®), midazolam (Versed®), pimozide (Orap®), triazolam (Halcion®), voriconazole (Vfend®), or ergot medicines (such as Sansert®, Ergostat®, Cafergot®, Wigraine®, Bellergal-S®, or DHE 45®).

How to Use This Medicine

Capsule, Tablet

• Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to. Efavirenz is used with other medicines to treat HIV infection. Make sure you take all of your medicines as your doctor has prescribed. Do not stop taking this medicine, even for a short time, unless your doctor tells you to.
• Take this medicine on an empty stomach, preferably at bedtime. Swallow this medicine with water. Take this medicine at the same time each day.

If a dose is missed:

• If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine

• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
• Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine after you have finished your treatment. You will also need to throw away old medicine after the expiration date has passed.
• Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• There are many other drugs that may interact with efavirenz. Using these drugs can cause problems that are serious, even life-threatening. Make sure your doctor knows about all other medicines you are using. Tell your doctor if you change a dose of another medicine, or stop taking another medicine. Your dose of efavirenz may need to be changed also.
• Make sure your doctor knows if you are using antibiotics (such as clarithromycin, rifabutin, rifampin, Biaxin®, Mycobutin®, Rifadin®, Rifamate®, or Rifater®), an estrogen hormone replacement (such as ethinyl estradiol or Estinyl®), a blood thinner (such as warfarin or Coumadin®), birth control pills, or St. John's wort. Tell your doctor if you are also using other medicines to treat HIV/AIDS (such as amprenavir, atazanavir, fosamprenavir, indinavir, lopinavir, ritonavir, saquinavir, Agenerase®, Crixivan®, Fortovase®, Invirase®, Kaletra®, Lexiva®, Norvir®, or Reyataz®).
• Make sure your doctor knows if you are also using medicine to treat seizures (such as carbamazepine, phenobarbital, phenytoin, Carbatrol®, Dilantin®, or Tegretol®), fungal infections (such as itraconazole, ketoconazole, Nizoral®, or Sporanox®), or depression (such as sertraline or Zoloft®). Tell your doctor if you are also using certain blood pressure medicines (such as diltiazem, felodipine, nicardipine, nifedipine, verapamil, Adalat®, Calan®, Cardene®, Cardizem®, Covera HS®, Isoptin SR®, Plendil®, Procardia®, Tiazac®, or Verelan®), medicine to lower cholesterol (such as atorvastatin, pravastatin, simvastatin, Lipitor®, Pravachol®, or Zocor®), or pain medicine (such as methadone or Dolophine®).
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine

• Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.
• You should not breast feed if you have HIV or AIDS, because you may give the infection to your baby through your breast milk.
• Tell your doctor if you have a history of liver disease or hepatitis. Make sure your doctor knows if you have a history of seizures, mental illness, emotional problems, or drug abuse. Tell your doctor if you are currently using alcohol. Make sure your doctor knows about any other medical problems you currently have, or have had in the past.
• When you start taking HIV medicines, your immune system may get stronger. If you have infections that are hidden in your body, such as pneumonia or tuberculosis, you may notice new symptoms when your body tries to fight them. If this occurs, be sure to tell your doctor.
• This medicine will not keep you from giving HIV to your partner during sex. Make sure you understand and practice safe sex, even if your partner also has HIV. Do not share needles with anyone.
• Birth control pills may not work as well while you are using efavirenz. To keep from getting pregnant, use another form of birth control. Other forms include condoms, a diaphragm, or a contraceptive foam or jelly.
• This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
• Your doctor will need to check your blood at regular visits while you are using this medicine. Be sure to keep all appointments.
• Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
• Blistering, peeling, or red skin rash.
• Confusion, trouble thinking clearly, or hallucinations (seeing or hearing things that are not there).
• Dark-colored urine or pale stools.
• Fast or pounding heartbeat.
• Fever or cough.
• Lightheadedness or fainting.
• Seizures or tremors.
• Severe depression (sadness), anxiety, nervousness, mood changes, problems dealing with anger, or thoughts of hurting yourself or others.
• Sudden and severe stomach pain, nausea, or vomiting.
• Yellowing of your skin or the whites of your eyes.

If you notice these less serious side effects, talk with your doctor:

• Diarrhea, stomach pain, or upset stomach.
• Dizziness or headache.
• Gaining weight around your neck, upper back, breast, face, or waist.
• Joint or muscle pain.
• Mild skin rash or itching.
• Problems with balance or walking.
• Sleepiness or unusual drowsiness.
• Tiredness.
• Trouble sleeping or concentrating, strange dreams.