Efavirenz
Antiviral, Systemic · Non-nucleoside reverse transcriptase inhibitor
Indications
Antiviral combination treatment of HIV-1 infected adults, adolescents & children.
Dosage
Adults: In combination with protease inhibitor &/or nucleoside analogue reverse transcriptase inhibitors (NRTls): 600 mg once daily. Adolescent & Children: < 17 yr: Combination therapy with protease inhibitor &/or NRTls: >40 kg: 600 mg once daily; 32.5 - <40 kg: 400 mg once daily; 25 - <32.5 kg: 350 mg once daily, 20 - <25 kg: 300 mg once daily; 15 - <20 kg: 250 mg once daily; 13 - <15 kg: 200 mg once daily. Children <3 yr or <13 kg: No studies. Children <40 kg: Tab formulation unsuitable.
Adverse Effects
Dizziness, nausea, headache, fatigue, rash including erythema multiforme & Stevens-Johnson Syndrome, allergic reaction, abnormal coordination, ataxia, confusion, stupor, vertigo, vomiting, diarrhoea, hepatitis, impaired concentration, insomnia, anxiety, abnormal thinking, agitation, amnesia, delirium, emotional liability, euphoria, hallucination & psychosis. Raised liver enzymes and serum amylase, hepatic failure, lipodystrophy, metabolic abnormalities.
Risk Factor (Pregnancy/Lactation)
Pregnancy: Positive evidence of risk: Use only when no safer alternative exists for a serious problem. Lactation: Contraindicated or not recommended. Contraindications: Moderate to severe hepatic impairment. Family history of sudden death or congenital QT prolongation, other risk factors for QT prolongation. Life-threatening cutaneous reaction to previous NNRTIs. History of cardiac disease. Severe electrolyte imbalance. Precautions: Must not be used as a single agent to treat HIV or added on as a sole agent to a failing regimen. If any antiretroviral medication in a combination regimen is interrupted because of suspected intolerance, serious consideration should be given to simultaneous discontinuation of all antiretroviral medications. Prophylaxis with appropriate antihistamines prior to initiating therapy in children may be considered. Monitor psychiatric adverse experiences, nervous…
Interactions
Amprenavir, indinavir, ritonavir, rifamycin, clarithromycin, oral contraceptives, anticonvulsants, methadone, St. John's Wort, midazolam, pimozide, ergot alkaloids, voriconazole, itraconazole, posaconazole, grapefruit juice, protease inhibitors, rifampicin, rifabutin, phenytoin, phenobarbital, carbamazepine, statins, simeprevir, sertraline, cetirizine, lorazepam, inhibitors or substrates of CYP3A4 or CYP2B6, other NNRTIs, immunosuppressants, warfarin, acenocoumarol, atovaquone/proguanil, bupropion, drugs known to prolong the QT interval (e.g., antiarrhythmics, antipsychotics, antidepressants, fluoroquinolones, macrolides, flecainide).
Advice to Patient
Take with or without meals, preferably at bedtime. Do not give infant formula within 2 hours after giving this medication to baby using capsule sprinkle method. Take missed dose as soon as you remember, unless it is time for the next dose. Do not take double dose. Contact prescriber if there is acute headache, dizziness, unusual dreams, fatigue, sleepiness, amnesia, hallucinations, seizures, confusion, emotional instability, feeling of hopelessness or anxiousness, suicidal thoughts, tremors, weakness, muscle pain, rash, numbness, changes in body fat or increased cholesterol level, dark coloured urine, yellowing of skin or eyes, pale stools, loss of appetite, lower abdominal pain. Follow recommended schedule of all medications as this medication is used in combination with other medications. Avoid alcohol during therapy. Take sufficient amount of fluids (2-3 litres per day) to maintain…
Pharmacokinetics
Absorption: Increased by high-fat/high-caloric meals. Metabolism: Hepatic. Bioavailability: 42%. Half-life elimination: Single dose: 52-76 hrs. Multiple doses: 40-55 hrs. Time to peak: 3-5 hrs. Excretion: Faeces (16%-61%). Urine (approx. 14%-34%).
Brands with this active ingredient
Compiled by Healify Pharmacy from published drug references. How we compile it →
Always consult a pharmacist or doctor.