Classifications: antiretroviral agent; nonnucleoside reverse transcriptase inhibitor (nnrti); Therapeutic:antiretroviral; nnrti
Pregnancy Category: D
50 mg, 100 mg, 200 mg capsules; 300 mg, 600 mg tablets
Nonnucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1. Binds directly to reverse transcriptase and blocks RNA polymerase
activities of the HIV-1 virus, thus preventing replication of the virus.
Prevents replication of the HIV-1 virus. HIV-2 reverse transcriptase and DNA polymerases alpha, beta, gamma, and delta are
not inhibited by efavirenz. Resistant strains appear rapidly. Effectiveness is indicated by reduction in viral load (plasma
level HIV RNA).
HIV-1 infection in combination with other antiretroviral agents.
Hypersensitivity to efavirenz; pregnancy (category D), lactation.
Liver disease, alcoholism, hepatitis, hypertriglyceridemia, hypercholesterolemia, substance abuse, antimicrobial resistance,
bipolar disorder, depression, suicidal ideation, exfoliative dermatitis; females of childbearing age, CNS disorders; history
of seizures. Safety and efficacy in children <3 y old or who weigh <13 kg (29 lb) are not known.
Route & Dosage
Adult: PO 600 mg q.d.
Child: PO ≥3 y, 1015 kg, 200 mg q.d.; 1520 kg, 250 mg q.d.; 2025 kg, 300 mg q.d.; 2532.5 kg, 350 mg q.d.; 32.540 kg, 400 mg q.d.; >40 kg, 600 mg q.d.
- Use bedtime dosing to increase tolerability of CNS adverse effects.
- Give exactly as ordered. Do not skip a dose or discontinue therapy without consulting the physician.
- Do not give efavirenz following a high fat meal.
- Store at 15°30° C (59°86° F) in a tightly closed container and protect from light.
Adverse Effects (≥1%)Body as a Whole: Fatigue
, fever. CNS:
Dizziness, headache, hypoesthesia, impaired concentration, insomnia
, abnormal dreams, somnolence, depression
adverse psychiatric experiences. CV:
Hypercholesterolemia. GI: Nausea,
dyspepsia, abdominal pain, flatulence, anorexia, increased liver function tests (ALT, AST). Respiratory:
Cough. Skin: Rash
(erythematous rash, pruritus, maculopapular rash, erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis
), increased sweating. Urogenital:
Renal calculus, hematuria.
Diagnostic Test Interference
False-positive urine tests for marijuana.
Decreased concentrations of clarithromycin, indinavir, nelfinavir, saquinavir, voriconazole;
increased concentrations of ritonavir, azithromycin, ethinyl estradiol.
Efavirenz levels are increased by ritonavir, fluconazole
and decreased by saquinavir, rifampin.
Additional drugs not recommended for administration with efavirenz include midazolam, triazolam, ergot derivatives
, warfarin. Herbal: St. John's wort
may decrease antiretroviral activity.
5 h; steady-state 610 d. Distribution:
99% protein bound. Metabolism:
In liver by cytochrome P450 3A4 and 2B6; can induce (increase) its own metabolism. Elimination:
1434% in urine, 1661% in feces. Half-Life:
5276 h after single dose, 4055 h after multiple doses.
Assessment & Drug Effects
- Monitor for suicidal ideation in patients who are depressed, or who have a history of depression.
- Monitor GI status and evaluate ability to maintain a normal diet.
- Lab tests: Periodic liver functions and lipid profile.
Patient & Family Education
- Contact physician promptly if any of the following occurs: skin rash, delusions, inappropriate behavior, thoughts of suicide.
- Use or add barrier contraception if using hormonal contraceptive.
- Notify physician immediately if you become pregnant.
- Do not drive or engage in potentially hazardous activities until response to the drug is known. Dizziness, impaired concentration,
and drowsiness usually improve with continued therapy.