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a non-nucleoside reverse transcriptase inhibitor, used as an antiretroviral in treatment of human immunodeficiency virus infection; administered orally.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.



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.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


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.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


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.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


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.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
Pharmacogenetics-based population pharmacokinetic analysis of efavirenz in HIV-1-infected individuals.
The introduction of Symfi comes after the US FDA's approval of the company's Cimduo (lamivudine and tenofovir disoproxil fumarate) in 300 mg/300 mg tablets and Symfi Lo (efavirenz, lamivudine and tenofovir disoproxil fumarate) in 400 mg/300 mg/300 mg tablets for patients with HIV-1 in adults and pediatric patients weighing at least 35 kg.
Her antiretroviral regimen is comprised of Tenofovir Disoproxil Fumarate 300 mg (TDF), Lamivudine 300 mg, and Efavirenz 600 mg in a single pill combination tablet (TELURA[R], Mylan).
concluded that antiretroviral therapy with nevirapine or efavirenz showed similar efficacy, so triple-drug regimens with either NNRTI are valid for first-line treatment.
The three ART molecules likely to induce drug eruptions in our series were Nevirapine, Efavirenz, and Zidovudine.
AIDS: Acquired immunodeficiency syndrome ART: Antiretroviral therapy CI: Confidence intervals EFV: Efavirenz HIV: Human Immunodeficiency Virus NVP: Nevirapine PLWHA: People living with HIV AIDS RR: Relative risk TDF: Tenofovir disoproxil fumarate TDF/3TC (FTC)/EFV: Tenofovir disoproxil fumarate plus Lamivudine or Emtricitabine plus Efavirenz TDF/3TC (FTC)/NVP: Tenofovir disoproxil fumarate plus lamivudine or emtricitabine plus nevirapine WHO: World Health Organization ZDV: Zidovudine ZDV/3TC/NVP: Zidovudine plus lamivudine plus nevirapine ZDV/3TC/EFV: Zidovudine plus lamivudine plus efavirenz.
"The impact of efavirenz exposure was particularly high in those with a prior psychiatric diagnosis," according to the infectious diseases specialist.
Out of these, 185 patients were getting Tenofovir, Lamivudine and Nevirapine regimen and 15 patients were under Tenofovir, Lamivudine and Efavirenz regimen.
She was on the standard first-line regimen comprising abacavir, lamivudine and efavirenz (EFV), each of which was dosed appropriately according to her weight and the Southern African HIV Clinicians Society guidelines.
Efavirenz (EFV) has demonstrated high antiretroviral efficacy in several clinical trials and is currently a first-line drug for treatment of human immunodeficiency virus (HIV) infection in several countries.
Efavirenz is a non-nucleoside reverse transcriptase inhibitor that produces its antiretroviral activity by binding directly to the enzyme reverse transcriptase, thus inhibiting replication of the virus.