Also found in: Dictionary, Acronyms, Wikipedia.


a non-nucleoside reverse transcriptase inhibitor, used as an antiretroviral in treatment of human immunodeficiency virus infection; administered orally.



Pharmacologic class: Nonnucleoside reverse transcriptase inhibitor

Therapeutic class: Antiretroviral

Pregnancy risk category D


Inhibits human immunodeficiency virus (HIV) reverse transcriptase (required for transcription of HIV-1 RNA to DNA), leading to viral cell death


Capsules: 50 mg, 200 mg

Tablets: 600 mg

Indications and dosages

HIV infection (given with one or more additional antiretrovirals)

Adults and children older than age 3 and weighing more than 40 kg (88 lb): 600 mg P.O. once daily

Children weighing 32.5 to 40 kg (71.5 to 88 lb): 400 mg P.O. once daily

Children weighing 25 to 32.5 kg (55 to 71.5 lb): 350 mg P.O. once daily

Children weighing 20 to 25 kg (44 to 55 lb): 300 mg P.O. once daily

Children weighing 15 to 20 kg (33 to 44 lb): 250 mg P.O. once daily

Children weighing 10 to 15 kg (22 to 33 lb): 200 mg P.O. once daily

Dosage adjustment

• Concurrent use of rifampin or voriconazole


• Hypersensitivity to drug
• Concurrent use of astemizole, cisapride, midazolam, triazolam, ergot derivatives, voriconazole, or bepridil


Use cautiously in:
• hypercholesterolemia, hepatic impairment, concurrent use of hepatotoxic drugs, mental illness, or substance abuse
• concurrent use of St. John's wort (use not recommended)
• pregnant or breastfeeding patients
• children.


• Give on empty stomach.
• Know that drug is given with other antiretrovirals.

Adverse reactions

CNS: dizziness, drowsiness, fatigue, insomnia, abnormal dreams, hypoesthesia, depression, headache, poor concentration, nervousness, anxiety, CNS depression, suicidal ideation

CV: arrhythmias

GI: nausea, diarrhea, flatulence, abdominal pain, dyspepsia

GU: hematuria, renal calculi

Hepatic: hepatotoxicity

Respiratory: respiratory depression

Skin: rash, diaphoresis, pruritus,erythema multiforme, toxic epidermal necrolysis, Stevens-Johnson syndrome

Other: increased appetite


Drug-drug.Azole antifungals (ketoconazole, voriconazole): decreased antifungal plasma concentration, increased efavirenz plasma concentration

Calcium channel blockers: possible decreased calcium channel blocker concentration

Clarithromycin, indinavir: reduced blood levels of these drugs

CNS depressants (including antidepressants, antihistamines, opioids): increased CNS depression

CYP450 inducers (including phenobarbital, rifabutin, rifampin): increased clearance and decreased blood level of efavirenz

CYP450 inhibitors, ergot alkaloids, estrogen, midazolam, ritonavir, triazolam: increased blood levels of these drugs, greater risk of serious adverse reactions (including arrhythmias, CNS and respiratory depression, and hepatotoxicity)

HMG-CoA reductase inhibitors: decreased plasma concentration of atorvastatin, pravastatin, and simvastatin

Hormonal contraceptives: increased ethinyl estradiol blood level

Protease inhibitors: decreased plasma level and efficacy of these drugs

Saquinavir: decreased saquinavir blood level

Warfarin: increased or decreased warfarin effects

Drug-diagnostic tests.Alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, total cholesterol, triglycerides: increased levels

Urine cannabinoid test: false-positive result

Drug-food.High-fat meal: increased drug absorption

Drug-herbs.St. John's wort: decreased efavirenz blood level and efficacy, drug resistance

Drug-behaviors.Alcohol use: increased CNS depression

Patient monitoring

• Monitor dietary intake and hepatic and lipid profile.
• Closely monitor patients with hepatic failure.

Record mood changes and stay alert for suicidal ideation or behavior.
• Be aware that drug may cause hypercholesterolemia.
• Know that amount of HIV in blood may increase if patient stops drug therapy even briefly.

Patient teaching

• Instruct patient to take with full glass of water, preferably at bedtime to improve tolerance of CNS effects. Also tell him to avoid taking drug with high-fat meals.
• Inform patient that drug must be taken in combination with other antiretrovirals.
• Tell patient that drug doesn't cure HIV or AIDS and that he can still transmit virus to others.

Advise patient to report suicidal thoughts and other psychiatric symptoms.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

Tell female patient to immediately inform prescriber if she becomes pregnant.
• Advise female patient to use adequate contraceptive measures for 12 weeks after discontinuing drug.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, herbs, and behaviors mentioned above.


/ef·a·vi·renz/ (ef´ah-vi″renz) an antiretroviral, inhibiting reverse transcriptase; used in the treatment of HIV infection.


An antiviral drug, C14H9ClF3NO2, that is a non-nucleoside reverse transcriptase inhibitor and is used in combination with other drugs for the treatment of HIV infection.


an antiviral.
indications It is used to treat HIV-1 in combination with other antiretroviral agents.
contraindications Known hypersensitivity to this drug prohibits its use.
adverse effects Adverse effects include abdominal pain, headache, dizziness, fatigue, impaired concentration, insomnia, abnormal dreams, and depression. Common side effects include diarrhea, nausea, and rash.


Sustiva AIDS A reverse transcriptase inhibitor used with other antivirals–eg, zidovudine, lamivudine for HIV-1 infection Adverse effects N&V, maculopapular rash, fatigue, headache, dizziness. See Non-nucleoside reverse transcriptase inhibitor.


A non-nucleoside reverse transcriptase inhibitor used, in combination with other antiretroviral drugs, to treat HIV infections. The drug is on the WHO official list. A brand name is Sustiva.
References in periodicals archive ?
It is predictable that new strategies for HIV treatment will comprise this dose reduction to Efavirenz 400 mg.
The plasma level of efavirenz is thought to play a role in the development of NPSEs, as are genetic polymorphisms in certain population groups.
The study found that efavirenz is ten times more toxic to brain cells and damages the dendritic spines of neurons.
Researchers looked for levels of the drug and its various metabolites, which are substances created when efavirenz is broken down by the liver.
He reported mood swings since starting treatment and said the efavirenz was making him feel 'crazy'.
17 Given the low baseline prevalence of neural tube defects, many more first-trimester efavirenz exposures would be required to quantify the risk.
At 192 weeks, the proportion of patients who met that target viral load reduction was 214 of 280 in the raltegravir group (76%) and 189 of 282 in the efavirenz group (67%), he reported.
At 48 weeks, the proportion of patients with fewer than 50 copies/mL of viral RNA as calculated by intent-to-treat analysis--the trial's primary end point--was significantly higher with efavirenz than it was with lopinavir/ritonavir (71% and 53%, respectively).
The study established efavirenz plus two NRTIs as an effective option for treatment in treatment-naive patients.
Lula said that the compulsory licensing of Efavirenz was a legitimate and necessary measure to guarantee that all patients had access to the drug.
In announcing its intention to issue a compulsory license for Merck's AIDS drug Efavirenz, Brazil is once again leading the way to affordable AIDS drug access for every nation," added Michael Weinstein, President of AIDS Healthcare Foundation.