Efavirenz (Sustiva) is a medication that's used in combination with other antiretroviral (ARV) therapy to treat human immunodeficiency virus (HIV) infections. It comes as oral tablets and capsules that are swallowed whole. The capsules can also be opened up and sprinkled in liquid for people who have trouble swallowing. Some side effects of this medication are rash, diarrhea, and nausea. Efavirenz (Sustiva) is available as both a brand-name and generic medication.
Treatment of HIV infection in people ages 3 months and older
Efavirenz (Sustiva) is a non-nucleoside reverse transcriptase inhibitor (NNRTI). It blocks an enzyme found in HIV called reverse transcriptase that usually helps the virus make copies of itself. By blocking reverse transcriptase, efavirenz (Sustiva) prevents the HIV virus from doing so and from spreading.
Source:Â DailyMed
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:
Rare
Abdominal or stomach pain
blistering
changes in vision
clumsiness or unsteadiness
confusion
convulsions (seizures)
dark urine
delusions
double vision
fainting
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
yellow eyes or skin
Incidence not known
Actions that are out of control
attack, assault, or force
continuing vomiting
decreased awareness or responsiveness
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
irregular heartbeat recurrent
irritability
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
mimicry of speech or movements
mutism
negativism
nervousness
peculiar postures or movements, mannerisms, or grimacing
severe sleepiness
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:
Less common or rare
Abnormally decreased sensitivity, particularly to touch
agitation or anxiety
belching
change in sense of taste or smell
false sense of well-being
flaking and falling off of the skin
flushing
general feeling of discomfort
indigestion
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
weakness
Incidence not known
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.
Only taken once a day
Capsule form can be opened and sprinkled on soft food or liquid, such as applesauce or milk, so convenient for people with difficulty swallowing pills
Available as a lower-cost generic medication
Can be used in young children 3 months and older who weigh over 7.7 lbs
Has many potentially serious side effects and risks (e.g., nerve issues, irregular heartbeat)
Needs to be taken on an empty stomach
Not recommended during pregnancy
Interacts with a lot of medications
If you have trouble swallowing, open efavirenz (Sustiva) oral capsules and mix the content with 1-2 teaspoons of soft food (apple sauce) or liquid (infant formula, water). Take the entire mixture within 30 minutes of mixing. Finally, add small amounts of food or liquid to any leftovers, stir, and take again to make sure you got all the medication. Avoid eating for 2 hours after taking a dose of efavirenz (Sustiva).
Take efavirenz (Sustiva) on an empty stomach at bedtime to lower the risk of certain side effects from this medication.
If your child is taking efavirenz (Sustiva), tell their provider if your child experiences any changes in weight. Your child's dose is based on their weight, so the dose might need to be changed depending on how much the change in weight is.
Make sure to get your routine blood tests done on time while you’re taking efavirenz (Sustiva). This helps your provider make sure the medication is working for you and not causing side effects.
Tell your provider immediately if you experience symptoms of seizure, depression, or changes in mood while taking efavirenz (Sustiva).
Efavirenz (Sustiva) can cause you to feel dizzy and lightheaded. Avoid driving or do activities that require a lot of focus until you know how this medication affects you.
Let your provider or pharmacist know what medications you're taking or planning to take, including over-the-counter products and supplements. Efavirenz (Sustiva) can interact with many medications. These interactions can affect how well your medications work or how safe they are for you.
Talk to your provider before stopping efavirenz (Sustiva) or any of your HIV medications. Doing so can cause the virus to spread and become harder to treat.
Efavirenz (Sustiva) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: History of heart problems, slow heart rate, or other abnormal heart rhythms (arrhythmias) | Personal or family history of long QT syndrome | Taking other medications that cause QT prolongation
Efavirenz (Sustiva) can affect your heart rhythm, which can be serious and life-threatening. One example includes lengthening the time it takes for your heart to pump and then relax. This is known as QT prolongation. Your risk for QT prolongation is higher if you have certain factors, including heart rhythm problems or are taking other medications that cause heart rhythm problems, such as amiodarone (Pacerone), among others. If you feel your chest pounding, have trouble breathing or chest pain, or feel faint or lightheaded while taking efavirenz (Sustiva), call 911 right away.
Risk factors: History of seizures, nerve damage, or mental health | Medical conditions that raise the risk of seizures | Taking mental health medications or medications that raise the risk of seizures | Injection drug use
Though rare, efavirenz (Sustiva) can raise your risk of seizures, dizziness, abnormal dreams, hallucinations, and trouble sleeping. For people who do experience these side effects, symptoms are likely to happen in the first 1-2 days of treatment and usually go away after 2-4 weeks.
Efavirenz (Sustiva) can also put you at risk for nerve damage that can affect your balance or cause confusion. These nerve problems can occur month to years after starting treatment. Talk to your provider right away if you experience dizziness, trouble concentrating, or drowsiness after starting this medication.
In addition, efavirenz (Sustiva) can also raise your risk of depression, suicidal thoughts or behavior, aggressive behavior, psychosis, and nervousness. These changes in behavior or thoughts are more likely to happen if you have a history of mental health or are taking medications for mental health. If you experience any of these side effects, seek medical help right away or contact your provider. They can help manage your treatment.
Taking efavirenz (Sustiva) during early pregnancy might raise the risk for birth defects called neural tube defects in babies. Because of this potential risk, you're recommended to avoid getting pregnant during treatment and for 3 months after the last dose.
If you're able to have a child, your provider will ask you to take a pregnancy test to check if it's safe for you to take efavirenz (Sustiva). You'll need to use 2 forms of effective birth controls during your treatment with efavirenz (Sustiva). Keep in mind that efavirenz (Sustiva) can cause hormonal birth controls to not work as well. If you're pregnant or are planning to become pregnant, discuss your HIV treatment options with your provider.
Efavirenz (Sustiva) can sometimes cause rash and other severe skin reactions. These reactions typically appear in the first 2 weeks of treatment and usually resolve within a month. If you have a mild or moderate rash, continue to take efavirenz (Sustiva) and let your provider know. If you have a severe rash or your rash gets worse, talk with your provider right away. In rare cases, if you experience a severe rash with fever, general discomfort, muscle or joint pain, mouth sores, blisters, or facial swelling, stop taking efavirenz (Sustiva) right away and get medical attention.
Risk factors: Hepatitis B or C | History of liver problems
Efavirenz (Sustiva) can cause life-threatening liver problems. Your provider will order blood tests for you before and during treatment so they can make sure this medication is safe for your liver. Let your provider know immediately if you experience signs and symptoms of liver damage, such as feeling sleepy, nausea, loss of appetite, light-colored stool, upper right stomach pain, yellowing of the skin or eyes, or dark urine.
Efavirenz (Sustiva) raises the amount of cholesterol and triglycerides (fats) in your blood, which can put you at higher risk for a heart attack or stroke. Your provider will monitor your blood works before and during treatment with this medication to make sure it's safe for you. If your cholesterol levels are too high, your might need to take medications to help keep them under control. Keep in mind that certain cholesterol medications, such as atorvastatin, pravastatin, and simvastatin (Zocor), might not work as well when taken with efavirenz (Sustiva). Make sure to let your provider know all the medications you're taking before being prescribed new ones.
Rarely, people taking HIV medications, such as efavirenz (Sustiva), have experienced changes in body fat. These changes include fat buildup in the back of the neck, breast, and around the middle of the body. Some people also lost fat from the legs, arms, and face. It's not clear whether efavirenz (Sustiva) causes these changes to body fat, why this happens, and whether it will affect your health in the future. Let your provider know if these changes occur while you're taking efavirenz (Sustiva).
Taking combination ARV therapy, such as efavirenz (Sustiva) with other HIV medications, can cause changes to your immune system called immune reconstitution syndrome. This condition happens when your immune system becomes overly active after you start combination therapy. So your immune system begins to fight off different infections that it was too weak to fight off before you started treatment. In rare cases, your immune response might improve too much with treatment that it starts to attack normal cells in your body (autoimmune). You can develop these conditions as early as during the first few weeks of treatment or many months later. Tell your healthcare provider right away if you start having any new symptoms, such as fever, pain, hair loss, bulging eyes, or sweating, after starting efavirenz (Sustiva).
Some medications can interfere with how well your body gets rid of efavirenz (Sustiva) from your system. This can affect the amount of efavirenz (Sustiva) in your body, how well it works, and the risk of side effects.
Taking certain anti-seizure medications (e.g., carbamazepine (Tegretol)) or tuberculosis medication (e.g., rifampin (Rifadin)) can lower the amount of efavirenz (Sustiva) in your body. This can make efavirenz (Sustiva) not work as well to treat your HIV. So this combination must be avoided.
Efavirenz (Sustiva) also interferes with how your body gets rid of other medications. For example, taking efavirenz (Sustiva) with medications like diltiazem (Cardizem) can lower the amount of diltiazem in your body. This can cause your blood pressure to not be controlled. In addition, taking efavirenz (Sustiva) with warfarin (Coumadin) can either raise or lower the amount of warfarin in your body. Your provider might need to adjust your dose of the blood thinner and monitor your blood works more closely during treatment.
Because of the potential for interactions with efavirenz (Sustiva) and various medications, tell your provider and pharmacist about all the medications you take or plan to take. They can make sure your medications are safe to take together.
Adults: The typical dose is 600 mg by mouth once daily at bedtime on an empty stomach.
Children (ages 3 months and older who weigh at least 7.7 lbs): Your child's provider will determine the dose based on your child's body weight. Typically, dosage ranges from 100 mg to 600 mg by mouth once daily at bedtime on an empty stomach.
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.
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.
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.
Taken at the same time as Zepatier (elbasvir / grazoprevir)
Treatment of HIV infection in people ages 3 months and older
Treatment of HIV-1 infection in people 2 years and older, weighing at least 30 pounds, with an HIV viral load of less than 100,000 copies/mL and who haven't taken HIV medications before
Short-term treatment of HIV-1 infection in certain people ages 12 years and older, weighing at least 77 pounds, who are planning to start or planning to miss a dose of Cabenuva (cabotegravir / rilpivirine)
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