Sustiva Side Effects

Generic Name: efavirenz

Note: This page contains side effects data for the generic drug efavirenz. It is possible that some of the dosage forms included below may not apply to the brand name Sustiva.

It is possible that some side effects of Sustiva may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

For the Consumer

Applies to efavirenz: oral capsule, oral tablet

As well as its needed effects, efavirenz (the active ingredient contained in Sustiva) may cause unwanted side effects that require medical attention.

If any of the following side effects occur while taking efavirenz, check with your doctor immediately:

More common
  • Depression
  • skin rash or itching
Less common
  • Blood in the urine
  • difficult or painful urination
  • pain in the lower back or side
  • Abdominal or stomach pain
  • blistering
  • changes in vision
  • clumsiness or unsteadiness
  • confusion
  • convulsions (seizures)
  • cough
  • dark urine
  • delusions
  • double vision
  • fainting
  • fast or pounding heartbeat
  • fever or chills
  • headache (severe and throbbing)
  • hives
  • 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
  • tremor
  • troubled breathing
  • unusual tiredness
  • weight loss
  • yellow eyes or skin
Incidence not known
  • 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
  • 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
  • nervousness
  • talking, feeling, and acting with excitement

Some efavirenz side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

More common
  • Diarrhea
  • dizziness
  • drowsiness
  • headache
  • increased sweating
  • poor concentration
  • trouble sleeping
Less common or rare
  • Abnormally decreased sensitivity, particularly to touch
  • agitation or anxiety
  • belching
  • change in sense of taste or smell
  • dry mouth
  • excessive gas
  • false sense of well-being
  • flaking and falling off of the skin
  • flushing
  • general feeling of discomfort
  • heartburn
  • indigestion
  • joint pain
  • lack of feeling or emotion
  • loss of hair
  • loss of memory
  • loss of sense of reality
  • mood changes
  • pain
  • 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

For Healthcare Professionals

Applies to efavirenz: oral capsule, oral tablet


The most significant side effects associated with efavirenz (the active ingredient contained in Sustiva) have included nervous system symptoms, psychiatric symptoms, and rash. The most common side effects of at least moderate severity have included rash, dizziness, nausea, headache, fatigue, insomnia, and vomiting in greater than 5% of patients treated with efavirenz in combination with lamivudine-zidovudine or indinavir.

Nervous system

Very common (10% or more): Dizziness (any severity: 28.1%), insomnia (any severity: 16.3%)
Common (1% to 10%): Dizziness (moderate or severe intensity: up to 9%), impaired concentration (any severity: 8.3%; moderate or severe intensity: up to 5%), headache (moderate or severe intensity: up to 8%), insomnia (moderate or severe intensity: up to 7%), somnolence (any severity: 7%; moderate or severe intensity: up to 2%), abnormal dreams (any severity: 6.2%, moderate or severe intensity: up to 3%), hallucinations (any severity: 1.2%)
Rare (less than 0.1%): Vacuolar axonopathy and hypersomnolence leading to coma and death (at least 1 patient)
Frequency not reported: Amnesia, agitation, euphoria, depersonalization, confusion, abnormal thinking, stupor, vivid dreams, nightmares, impaired attention span
Postmarketing reports: Abnormal coordination, ataxia, cerebellar coordination and balance disturbances, convulsions, hypoesthesia, paresthesia, neuropathy, tremor, vertigo, tinnitus

Nervous system symptoms of any grade and regardless of causality (52.7%) included dizziness, insomnia, impaired concentration, somnolence, abnormal dreams, hallucinations, amnesia, agitation, euphoria, depersonalization, confusion, abnormal thinking, and stupor during clinical trials of efavirenz in combination with other antiretroviral agents. These symptoms were mild in 33.3%, moderate in 17.4%, and severe in 2% of patients. Therapy was discontinued in 2.1% of patients due to these side effects.

Nervous system symptoms generally begin the first or second day of therapy and often resolve after 2 to 4 weeks. Dosing at bedtime may improve the tolerability of these effects.

Vacuolar axonopathy and hypersomnolence leading to coma and death was reported in a patient with elevated efavirenz levels.


Treatment was discontinued in 1.7% of patients due to rash.

The median time to onset of rash in adults was 11 days. In most patients, the rash resolved within one month despite continued use of the drug. Patients who discontinue efavirenz (the active ingredient contained in Sustiva) therapy because of rash may be reinstated with the use of appropriate antihistamines and/or corticosteroids. The drug should be withdrawn if severe rash develops, such as that associated with blistering, desquamation, mucosal involvement, or fever.

There is limited experience with the use of efavirenz in patients who have previously discontinued other nonnucleoside reverse transcriptase inhibitors (NNRTIs) due to rash. In 19 such patients formerly on nevirapine, approximately half developed a mild to moderate rash, and two of them discontinued efavirenz because of the rash.

Very common (10% or more): Skin rash of any grade (26.3%), rash (includes erythema multiforme, rash, erythematous rash, follicular rash, maculopapular rash, petechial rash, pustular rash, urticaria, macules, papules, erythema, redness, inflammation, allergic rash, welts, hives, itchy, pruritus; moderate or severe intensity: up to 16%), Grade 2 rash (diffuse maculopapular rash, dry desquamation; 14.7%), Grade 1 rash (erythema, pruritus; 10.7%)
Common (1% to 10%): Pruritus (moderate or severe intensity: up to 9%)
Uncommon (0.1% to 1%): Grade 3 rash (vesiculation, moist desquamation, ulceration; 0.8%), Grade 4 rash (erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, necrosis requiring surgery, exfoliative dermatitis; 0.1%)
Frequency not reported: Nail disorders, skin discoloration, leukocytoclastic vasculitis
Postmarketing reports: Erythema multiforme, photoallergic dermatitis, Stevens-Johnson syndrome


Very common (10% or more): Depression (any severity: up to 19%), anxiety (any severity: up to 13%)
Common (1% to 10%): Nervousness (any severity: up to 7%; moderate or severe intensity: up to 2%), depression (moderate or severe intensity: up to 5%), anxiety (moderate or severe intensity: up to 4%), severe depression (2.4%)
Uncommon (0.1% to 1%): Suicidal ideation (0.7%), nonfatal suicide attempts (0.5%), aggressive behavior (0.4%), paranoid reactions (0.4%), manic reactions (0.2%)
Frequency not reported: Obsessive disorder, irritability, mood changes
Postmarketing reports: Aggressive reactions, agitation, delusions, emotional lability, mania, neurosis, paranoia, psychosis, suicide

Psychiatric symptoms generally begin the first or second day of therapy and often resolve after 2 to 4 weeks. Dosing at bedtime may improve the tolerability of these effects.

Psychiatric side effects classified as serious during controlled trials included severe depression, suicidal ideation, nonfatal suicide attempts, aggressive behavior, paranoid reactions, and manic reactions. One percent of patients discontinued or interrupted efavirenz treatment due to one or more of these side effects.


A 42-year-old HIV-positive woman's saquinavir in her highly active antiretroviral therapy was replaced with efavirenz (the active ingredient contained in Sustiva) to increase compliance. Two weeks following efavirenz initiation, the patient reported severe and constant burning in her tongue, gums, and oral mucosa and was diagnosed with burning mouth syndrome (BMS). Efavirenz therapy was discontinued and the BMS resolved within a week.

Very common (10% or more): Diarrhea (moderate or severe intensity: up to 14%)
Common (1% to 10%): Nausea (moderate or severe intensity: up to 10%), vomiting (moderate or severe intensity: up to 6%), dyspepsia (moderate or severe intensity: up to 4%), abdominal pain (moderate or severe intensity: up to 3%), anorexia (moderate or severe intensity: up to 2%)
Frequency not reported: Pancreatitis, burning mouth syndrome
Postmarketing reports: Constipation, malabsorption


Very common (10% or more): Pain (moderate or severe intensity: up to 13%)
Common (1% to 10%): Fatigue (moderate or severe intensity: up to 8%), elevated amylase (greater than 2 times ULN; up to 6%)
Frequency not reported: False positive urine drug screening test results for tetrahydrocannabinol and benzodiazepines, asymptomatic increases in serum amylase levels, vitamin D deficiency
Postmarketing reports: Flushing, contraceptive failure (with an implantable hormonal contraceptive), asthenia

False positive urine drug screening test results for tetrahydrocannabinol and benzodiazepines have been reported in HIV-infected patients receiving efavirenz. False positive cannabinoid test results have been observed with the CEDIA (Cloned Enzyme Donor ImmunoAssay) DAU Multilevel THC assay and the InstaCheck multidrug Screen Panel. The Triage 8 and the Drug Screen Multi 5 have shown false-positive results for benzodiazepines and tetrahydrocannabinol.


Common (1% to 10%): Increased ALT (greater than 5 times ULN; up to 8%), increased AST (greater than 5 times ULN; up to 8%), increased GGT (greater than 5 times ULN; up to 8%)
Postmarketing reports: Hepatic failure (a few reports were characterized by a fulminant course, with some cases progressing to transplantation or death), hepatic enzyme increase, hepatitis

Isolated elevations of GGT in patients receiving efavirenz may reflect the enzyme inducing effects of the drug not associated with liver toxicity.

During clinical trials, elevations in ALT and AST to greater than five times ULN occurred in 20% and 13%, respectively, of patients seropositive for hepatitis B and/or C treated with efavirenz. Treatment was discontinued in 3% of coinfected patients due to liver or biliary system disorders.

Some of the postmarketing reports of hepatic failure occurred in patients with no preexisting liver disease or other identifiable risk factors.


Common (1% to 10%): Neutropenia (less than 750/mm3; up to 10%)
Rare (less than 0.1%): Hemolytic anemia


Very common (10% or more): Increased nonfasting serum cholesterol (up to 54%), increased HDL (up to 35%), increased nonfasting triglycerides (greater than or equal to 751 mg/dL; up to 11%)
Common (1% to 10%): Increased glucose (greater than 250 mg/dL; up to 5%)
Frequency not reported: Redistribution/accumulation of body fat (including central obesity, dorsocervical fat enlargement, peripheral wasting, facial wasting, breast enlargement, "cushingoid appearance")
Postmarketing reports: Hypercholesterolemia, hypertriglyceridemia

Increased nonfasting serum cholesterol and HDL have been reported, although the clinical significance of these elevations is unknown.


Frequency not reported: QT interval prolongation, torsades de pointes
Postmarketing reports: Palpitations


Frequency not reported: Skin rash, eosinophilia, and systemic involvement (lymphadenopathy, interstitial nephritis, pneumonia, pulmonary infiltration, hepatitis, fever, rigor, myalgia, arthralgias)
Postmarketing reports: Allergic reactions


Frequency not reported: Osteomalacia (due to efavirenz-induced vitamin D deficiency)
Postmarketing reports: Arthralgia, myalgia, myopathy


Frequency not reported: Immune reconstitution syndrome, autoimmune disorders in the setting of immune reconstitution (e.g., Graves' disease, polymyositis, Guillain-Barre syndrome)


Rare (less than 0.1%): Renal colic, urolithiasis

Analysis of a 3 mm stone, eliminated by a 47-year-old HIV-1-infected male patient, showed a stone consisting of 60% efavirenz metabolites.


Postmarketing reports: Dyspnea


Postmarketing reports: Gynecomastia


Postmarketing reports: Abnormal vision


Rare (less than 0.1%): Podocyte damage (at least 1 report)

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