Efavirenz (Oral Route)
Original Article: http://www.mayoclinic.com/health/drug-information/DR601473
US Brand Names
Efavirenz is used in combination with other medicines for the treatment of the infection caused by the human immunodeficiency virus (HIV). HIV is the virus that causes acquired immune deficiency syndrome (AIDS).
Efavirenz will not cure or prevent HIV infection or AIDS; however, it helps keep HIV from reproducing and appears to slow down the destruction of the immune system. This may help delay the development of problems that usually result from AIDS or HIV disease. Efavirenz will not keep you from spreading HIV to other people. People who receive this medicine may continue to have some of the problems usually related to AIDS or HIV disease.
This medicine is available only with your doctor's prescription.
This product is available in the following dosage forms:
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of efavirenz in children younger than 3 years of age or those who weigh less than 13 kilograms (kg). Safety and efficacy have not been established.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of efavirenz in the elderly. However, elderly patients are more likely to have age-related kidney, liver, or heart problems, which may require caution and an adjustment in the dose for patients receiving efavirenz.
|All Trimesters||D||Studies in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy in a life threatening situation or a serious disease, may outweigh the potential risk.|
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Ergoloid Mesylates
- St John's Wort
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Ginkgo Biloba
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Estradiol Cypionate
- Estradiol Valerate
- Ethinyl Estradiol
- Ethynodiol Diacetate
- Medroxyprogesterone Acetate
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Alcohol or drug abuse, history of or
- Mental illness, history of—May increase the chance of having serious psychiatric side effects.
- Hepatitis B or
- Hepatitis C or
- Liver disease—Use with caution. Efavirenz may cause side effects to become worse.
- Hypersensitivity reactions (e.g., Stevens-Johnson syndrome, erythema multiforme, toxic skin eruptions), history of—Should not be used in patients with this condition.
- Seizures, history of—Use with caution. May increase chances of convulsions occurring.
Take this medicine exactly as directed by your doctor. Do not take it more often, and do not take it for a longer time than your doctor ordered. Also, do not change the dose or stop taking this medicine without checking first with your doctor. When your supply of this medicine is running low, contact your doctor or pharmacist ahead of time. Do not allow yourself to run out of this medicine.
This medicine comes with a patient information insert. Read and follow the instructions in the insert carefully. Ask your doctor if you have any questions.
Keep taking efavirenz for the full time of treatment even if you begin to feel better. It is also important that you continue taking all other medicines for HIV infection your doctor has instructed you to take. Efavirenz will not work if it is taken alone. It must be taken with other HIV medicines.
This medicine works best when there is a constant amount in the blood. To help keep blood levels constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times during the day. For example, if you or your child are taking one dose per day, try to take it at the same time each day. If you need help planning the best times to take your medicine, check with your doctor.
Efavirenz should be taken on an empty stomach because the amount of efavirenz absorbed into the body may be increased when taken with food, which might increase the chance of side effects.
Swallow the tablets whole with water. Do not break, crush, or chew it.
Take efavirenz at bedtime, especially during the first 2 to 4 weeks, to lessen central nervous system (CNS) side effects that may occur with this medicine. These effects usually lessen after you have been taking this medicine for awhile.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage forms (capsules or tablets):
- For treatment of HIV infection:
- Adults—600 milligrams (mg) once a day, taken with other medicines.
- Children 3 years of age and older (by weight)—
- 10 to 15 kilograms (22 to 33 pounds) of body weight: 200 mg once a day, taken with other medicines.
- 15 to 20 kilograms (33 to 44 pounds) of body weight: 250 mg once a day, taken with other medicines.
- 20 to 25 kilograms (44 to 55 pounds) of body weight: 300 mg once a day, taken with other medicines.
- 25 to 32.5 kilograms (55 to 71.5 pounds) of body weight: 350 mg once a day, taken with other medicines.
- 32.5 to 40 kilograms (71.5 to 88 pounds) of body weight: 400 mg once a day, taken with other medicines.
- 40 kilograms (88 pounds) of body weight or over: 600 mg once a day, taken with other medicines.
- Children up to 3 years of age—Use and dose must be determined by your doctor.
- For treatment of HIV infection:
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
It is very important that your doctor check the progress of you or your child at regular visits, to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.
Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. You should not become pregnant while you are taking this medicine and for 12 weeks after stopping it. If you think you have become pregnant while using the medicine, tell your doctor right away. Your doctor may want you to join a pregnancy registry for patients taking an anti-HIV medicine.
Do not use this medicine if you or your child are also using Atripla®, bepridil (Vascor®), cisapride (Propulsid®), ergot medicines (e.g., dihydroergotamine, ergonovine, ergotamine, methylergonovine, Bellergal-S®, Cafergot®, DHE 45®, Ergostat®, Sansert®, or Wigraine®), midazolam (Versed®), pimozide (Orap®), triazolam (Halcion®), or voriconazole (Vfend®).
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (e.g., St. John's wort) or vitamin supplements.
This medicine may cause some people to become dizzy, lightheaded, drowsy, or less alert than they are normally. Even if taken at bedtime, it may cause some people to feel drowsy or less alert on arising. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert.
Check with your doctor before taking efavirenz with alcohol or other medicines that affect the central nervous system (CNS). The use of alcohol or other medicines that affect the CNS with efavirenz may worsen the side effects of this medicine, such as dizziness, poor concentration, drowsiness, unusual dreams, and trouble with sleeping. Some examples of medicines that affect the CNS are antihistamines or medicine for allergies or colds; sedatives, tranquilizers, or sleeping medicine; medicine for depression; medicine for anxiety; prescription pain medicine or narcotics; medicine for attention deficit and hyperactivity disorder; medicine for seizures or barbiturates; muscle relaxants; or anesthetics, including some dental anesthetics.
This medicine may increase your risk of having serious mental or behavioral problems. Tell your doctor if you or your child develop any mood changes, strange thoughts, or any unusual behavior while you are using this medicine.
Liver problems may occur while you are using this medicine. Stop using this medicine and check with your doctor right away if you or your child are having more than one of these symptoms: abdominal pain or tenderness; clay-colored stools; dark urine; a fever; a headache; itching; loss of appetite; nausea and vomiting; skin rash; swelling of the feet or lower legs; unusual tiredness or weakness; or yellow eyes or skin.
This medicine may increase the level of cholesterol and fats in your blood. If this condition occurs, your doctor may give you a medicine to lower the cholesterol and fats. Talk to your doctor if you have concerns.
When you or your child start taking HIV medicines, your immune system may get stronger. If or your child you have certain infections, 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 right away.
Efavirenz may cause you or your child to have excess body fat. Tell your doctor if you or your child notice changes in your body shape, such as an increased amount of fat in the upper back and neck, or around the chest and stomach area. You might also lose fat from the legs, arms, and face.
This medicine will not keep you from giving HIV to your partner during sex. Make sure you understand this and practice safe sex, even if your partner also has HIV, by using a latex condom or other barrier method. This medicine will also not keep you from giving HIV to other people if they are exposed to your blood. Do not re-use or share needles with anyone.
Birth control pills may not work as well while you are using efavirenz. Use an additional form of birth control along with your pills while you are taking this medicine and for 12 weeks after stopping it to keep from getting pregnant. Other forms of birth control include condoms, diaphragms, or contraceptive foams or jellies.
Stop using this medicine and check with your doctor right away if you or your child develop a skin rash; blistering, peeling, or loosening of the skin; red skin lesions; sores or ulcers on the skin; or fever or chills while you or your child are using this medicine.
Tell the doctor in charge that you or your child are taking this medicine before you have any medical tests. The results of some tests may be affected by this medicine.
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:More common
- Skin rash or itching
- Blood in the urine
- Difficult or painful urination
- Pain in the lower back or side
- Abdominal or stomach pain
- Changes in vision
- Clumsiness or unsteadiness
- Convulsions (seizures)
- Dark urine
- Double vision
- Fast or pounding heartbeat
- Fever or chills
- Headache (severe and throbbing)
- Inappropriate behavior
- Loss of appetite
- Mood or mental changes (severe)
- Muscle cramps or pain
- Nausea or vomiting
- Nerve pain
- Open sores
- Pain, tenderness, bluish color, or swelling of the leg or foot
- Rapid weight gain
- Seeing, hearing, or feeling things that are not there
- Sense of constant movement of self or surroundings
- Sores, ulcers, or white spots in the mouth or on the lips
- Speech disorder
- Swelling or tenderness in the upper abdominal or stomach area
- Swelling of the hands, arms, feet, or legs
- Thoughts of suicide or attempts at suicide
- Tightness in the chest
- Tingling, burning, numbness, or pain in the hands, arms, feet, or legs
- Tingling, burning, or prickling sensations
- Troubled breathing
- Unusual tiredness
- Weight loss
- Yellow eyes or skin
- Actions that are out of control
- Attack, assault, or force
- Continuing vomiting
- Delusions of persecution, mistrust, suspiciousness, or combativeness
- Difficult or labored breathing
- Early appearance of redness or swelling of the skin
- General feeling of tiredness or weakness
- Late appearance of rash with or without weeping blisters that become crusted, especially in sun-exposed areas of the skin, may extend to unexposed areas
- Light-colored stools
- Shortness of breath
- Talking, feeling, and acting with excitement
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:More common
- Increased sweating
- Poor concentration
- Trouble with sleeping
- Abnormally decreased sensitivity, particularly to touch
- Agitation or anxiety
- Change in sense of taste or smell
- Dry mouth
- Excessive gas
- False sense of well-being
- Flaking and falling off of the skin
- General feeling of discomfort
- Joint pain
- Lack of feeling or emotion
- Loss of hair
- Loss of memory
- Loss of sense of reality
- Mood changes
- Painful, red, hot, or irritated hair follicles
- Ringing in the ears
- Stomach discomfort
- Unusual dreams
- Difficulty having a bowel movement (stool)
- Discoloration of the fingernails or toenails
- Dizziness or lightheadedness
- Feeling of constant movement of self or surroundings
- Increased amount of fat in the upper back and neck, or around the chest and stomach area
- Lose fat from the legs, arms, and face
- Sensation of spinning
- Swelling of the breasts or breast soreness in both females and males
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.