HOW TO USE: Read the Patient Information Leaflet if available from your pharmacist before you start taking efavirenz and each time you get a refill. If you have any questions regarding the information, consult your doctor or pharmacist.Take this medication by mouth on an empty stomach, without food, usually once daily at bedtime or as directed by your doctor. Taking efavirenz with food increases the blood level of this medication, which may increase your risk of certain side effects. See Side Effects section.Swallow this medication whole with water. If you have difficulty swallowing the capsule, it may be opened and the contents mixed gently in a small amount (1 to 2 teaspoons) of soft food such as applesauce, grape jelly, or yogurt. After taking the mixed medication, add 2 more teaspoons of food to the empty mixing container. Swallow the remaining mixture to make sure that you get the entire dose. Swallow within 30 minutes of mixing. Do not eat any food for 2 hours after taking this medication. For babies who cannot eat solid foods, the contents may be mixed in 2 teaspoons of infant formula and drawn up into an oral syringe to be given to the baby. (See Patient Information Leaflet.)The dosage is based on your medical condition and response to treatment. In children, the dosage is also based on weight.It is very important to continue taking this medication (and other HIV medications) exactly as prescribed by your doctor. Do not skip any doses. Do not increase your dose, take this drug more often than prescribed, or stop taking it (or other HIV medicines) even for a short time unless directed to do so by your doctor. Skipping or changing your dose without approval from your doctor may cause the amount of virus to increase, make the infection more difficult to treat (resistant), or worsen side effects.This medication works best when the amount of drug in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals. To help you remember, take it at the same time each day.
SIDE EFFECTS: Dizziness, trouble sleeping, drowsiness, unusual dreams, and trouble concentrating may frequently occur. These side effects may begin 1-2 days after starting this medication and usually go away in 2-4 weeks. They are also reduced by taking efavirenz on an empty stomach at bedtime. Avoid alcohol and street drugs while taking efavirenz. They may worsen these side effects.Tiredness, headache, nausea, vomiting, and diarrhea may also occur.If any of these effects persist or worsen, tell your doctor or pharmacist promptly.Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Some people may experience worsening of a previous medical condition (such as an old infection) as their immune systems improve, or develop new conditions because their immune systems have become overactive. This reaction may occur at any time (soon after starting HIV treatment or many months later). Tell your doctor right away if you have any serious side effects, including: unexplained weight loss, persistent muscle aches/weakness, joint pain, numbness/tingling of the hands/feet/arms/legs, severe tiredness, vision changes, severe/persistent headaches, signs of infection (such as fever, chills, trouble breathing, cough, non-healing skin sores), signs of an overactive thyroid (such as irritability, nervousness, heat intolerance, fast/pounding/irregular heartbeat, bulging eyes, unusual growth in the neck/thyroid known as a goiter), signs of a certain nerve problem known as Guillain-Barre Syndrome (such as difficulty breathing/swallowing/moving your eyes, drooping face, paralysis, slurred speech).Infrequently, serious psychiatric symptoms may occur during efavirenz treatment, although it is unclear if they are caused by efavirenz. These effects may be seen especially in people who have mental/mood conditions. Tell your doctor immediately if any of these unlikely but serious side effects occur: mental/mood changes (such as depression, rare thoughts of suicide, nervousness, angry behavior, hallucinations).Tell your doctor immediately if any of these rare but serious side effects occur: signs of liver problems (such as persistent nausea/vomiting, stomach/abdominal pain, severe tiredness, yellowing eyes/skin, dark urine).Changes in body fat may occur while you are taking this medication (such as increased fat in the upper back and stomach areas, decreased fat in the arms and legs). The cause and long-term effects of these changes are unknown. Discuss the risks and benefits of treatment with your doctor, as well as the possible use of exercise to reduce this side effect.Efavirenz can commonly cause a rash that is usually not serious. In adults, a rash may occur in the first 2 weeks after starting treatment and if it is not serious, it will usually resolve in 4 weeks. In children, a rash may occur in the first 4 weeks after starting treatment. However, you may not be able to tell it apart from a rare rash that could be a sign of a severe reaction. Therefore, seek immediate medical attention if you develop any rash.A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, blisters, peeling skin, fever, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
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