efavirenz

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

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e·fa·vir·enz (-fävîr-nz)

n.

A non-nucleoside drug used to treat HIV infection.

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efavirenz,

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.

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efavirenz [ef´ah-vi″renz]

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

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efavirenz

Sustiva

Pharmacologic class: Nonnucleoside reverse transcriptase inhibitor

Therapeutic class: Antiretroviral

Pregnancy risk category C

Action

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

Availability

Capsules: 50 mg, 100 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

Contraindications

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

Precautions

Use cautiously in:
• hypercholesterolemia, hepatic impairment, concurrent use of hepatotoxic drugs, mental illness, or substance abuse
• pregnant or breastfeeding patients
• children.

Administration

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

Route	Onset	Peak	Duration
P.O.	Rapid	3-5 hr	24 hr

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

Interactions

Drug-drug. 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

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)

Hormonal contraceptives: increased ethinyl estradiol blood level

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.
• 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.

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efavirenz

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. Cf Non-nucleoside reverse transcriptase inhibitor.