Used For:

• Treatment of HIV-1 infection in adults and adolescents (>3 years, weight ≥ 35 kg)Used as part of combination antiretroviral therapy (cART), usually with:Tenofovir + Lamivudine/EmtricitabineOr other approved NRTI backbone

Adult Dosage:

• Efavirenz 600 mg orally once daily, at bedtime (preferably on an empty stomach, to reduce CNS side effects).

Contraindications:

• Known hypersensitivity to efavirenz or formulation excipientsSevere hepatic impairment (use caution; may worsen liver dysfunction)Pregnancy: avoid especially in the first trimester if alternative therapy available (risk of neural tube defects in animal studies)Concurrent use with certain medications that strongly induce or inhibit CYP450 enzymes (may reduce efficacy or increase toxicity)

Side Effects:

• Common Side EffectsCNS: Dizziness, vivid dreams, insomnia, drowsiness, impaired concentrationGastrointestinal: Nausea, vomiting, diarrhea, abdominal painDermatological: Rash (mild to moderate; usually resolves spontaneously)Fatigue, headache, depression, anxietySerious / Rare Side EffectsSevere psychiatric symptoms: depression, suicidal ideation, hallucinations (rare)Severe rash / Stevens–Johnson syndrome / toxic epidermal necrolysisHepatotoxicity: elevated liver enzymes, especially in patients with hepatitis B/C co-infectionHyperlipidemia and lipid metabolism changes with long-term use

Precautions:

• CNS effects: Take at bedtime to reduce impact on daytime functioningLiver function: Monitor in patients with chronic liver disease or hepatitis co-infectionPregnancy and breastfeeding: Use only if benefits outweigh risks; breastfeeding may transmit HIV to infantDrug interactions: Efavirenz is a CYP3A4 and CYP2B6 substrate – interacts with many drugs, including anticonvulsants, rifampicin, benzodiazepines, statins, and hormonal contraceptivesAdherence is critical: Missing doses may lead to drug resistance

Dietary Restrictions:

• Can be taken with or without food, but empty stomach at bedtime recommended to minimize CNS side effectsAvoid alcohol (↑ CNS depression and hepatotoxicity risk)Avoid herbal supplements like St. John’s Wort (reduces efavirenz effectiveness)Maintain a balanced diet and monitor lipids if on long-term therapy