Non-nucleoside reverse transcriptase inhibitor (1st gen) Pregnancy: Currently available data on pregnant women indicate no malformative or foeto/neonatal toxicity, and no observable teratogenicity was detected in rats and rabbits, but there are no adequate and well-controlled studies in pregnant women. Caution should be exercised when prescribing nevirapine to pregnant women. Hepatotoxicity is more frequent in women with CD4+ cell counts above 250 cells/mm³ with detectable HIV-1 RNA in plasma (50 or more copies/mL) — these conditions should be taken into consideration in the therapeutic decision. It is recommended that women living with HIV do not breast-feed their infants in order to avoid transmission of HIV. Evidence of impaired fertility was seen in rats in reproductive toxicology studies.

Nevirapine

Brand names: Viramune

Nevirapine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) used as part of combination antiretroviral therapy for HIV-1 infection.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 200 mg once daily for the first 14 days (lead-in), then 200 mg twice daily

Route: Oral

Frequency: Once daily for the first 14 days, then twice daily

Max: Not stated in the SPC section retrieved

SPC §4.2, patients 16 years and older. Must be given in combination with at least two additional antiretroviral agents. The 14-day lead-in period should be used because it has been found to lessen the frequency of rash. Nevirapine should be administered by physicians experienced in the treatment of HIV infection. DOSE MANAGEMENT: patients experiencing rash during the 14-day lead-in period of 200 mg/day should not have their dose increased until the rash has resolved, and the isolated rash should be closely monitored. The 200 mg once daily regimen should not be continued beyond 28 days, at which point an alternative treatment should be sought due to the possible risk of underexposure and resistance. Patients who interrupt dosing for more than 7 days should restart the recommended dosing regimen using the two-week lead-in period. There are toxicities that require interruption of nevirapine therapy (see SPC §4.4). MISSED DOSE: if recognised within 8 hours of when it was due, take as soon as possible; if more than 8 hours later, take only the next dose at the usual time. ELDERLY: not specifically investigated in patients over the age of 65. HEPATIC IMPAIRMENT: should not be used in severe hepatic impairment (Child-Pugh C); no dose adjustment necessary in mild to moderate impairment. ADMINISTRATION: tablets shall be taken with liquid and should not be crushed or chewed; may be taken with or without food. PAEDIATRIC: 200 mg tablets following the above schedule are suitable for larger children, particularly adolescents, below the age of 16 who weigh more than 50 kg or whose body surface area is above 1.25 m² (Mosteller formula). An oral suspension, dosed according to body weight or body surface area, is available for children in this age group weighing less than 50 kg or with body surface area below 1.25 m², and for patients less than 3 years old — verify paediatric dosing against a children's formulary.

Dose adjustments

Renal

For patients with renal dysfunction requiring dialysis, an additional 200 mg dose of nevirapine following each dialysis treatment is recommended. Patients with CLcr ≥ 20 mL/min do not require a dose adjustment.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients
Re-administration to patients who have required permanent discontinuation for severe rash, rash accompanied by constitutional symptoms, hypersensitivity reactions, or clinical hepatitis due to nevirapine
Severe hepatic impairment (Child-Pugh C), or pre-treatment ASAT or ALAT above 5 x ULN until baseline ASAT/ALAT are stabilised below 5 x ULN
Re-administration to patients who previously had ASAT or ALAT above 5 x ULN during nevirapine therapy and had recurrence of liver function abnormalities on re-administration
Co-administration with herbal preparations containing St John's wort (Hypericum perforatum)

Side effects

Skin: rash (very common, 12.5%); uncommonly Stevens-Johnson syndrome / toxic epidermal necrolysis (which may be fatal, 0.2%), angioedema, urticaria
Hepatobiliary: hepatitis, including severe and life-threatening hepatotoxicity (common, 1.9%); uncommonly jaundice; rarely fulminant hepatitis (which may be fatal)
Gastrointestinal: nausea, vomiting, abdominal pain, diarrhoea (common)
General/nervous system: pyrexia, fatigue, headache (common)
Immune system: hypersensitivity including anaphylactic reaction, angioedema and urticaria (common); rarely drug reaction with eosinophilia and systemic symptoms
Investigations: abnormal liver function tests (common); blood and lymphatic — granulocytopenia (common), anaemia (uncommon)

Interactions

St John's wort (Hypericum perforatum) — contraindicated; risk of decreased plasma concentrations of nevirapine and reduced clinical effect (SPC §4.3)
Oral contraceptives — nevirapine might lower plasma concentrations, so women of childbearing potential should not use oral contraceptives as the sole method of birth control (SPC §4.6)

Clinical monograph

How it works

It binds directly and non-competitively to HIV-1 reverse transcriptase, disrupting the enzyme's catalytic site and blocking conversion of viral RNA into DNA.

Prescribing in practice

It can cause severe, potentially fatal hepatotoxicity and serious skin reactions including Stevens-Johnson syndrome, especially in the first weeks, so a lead-in dosing period and close monitoring are required.
Risk of hepatic reactions is higher when started at higher CD4 counts, which influences the decision to initiate.
It is a CYP enzyme inducer with numerous drug interactions, including reduced efficacy of some hormonal contraceptives and interactions with other antiretrovirals.

Monitoring

Monitor liver function frequently during the early weeks of treatment and review urgently if rash or hepatic symptoms occur.

Counselling the patient

Seek urgent help if you develop a rash, fever, blistering, or yellowing of the skin or eyes.
Do not stop or change the dose without advice, and tell your clinician about all other medicines.

Evidence & guidelines

The hepatotoxicity and skin-reaction warnings and lead-in dosing are established in the SPC and reflected in HIV treatment guidance.

Reference: BHIVA; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways