Causality assessment · Causality: well established

Nevirapine and Hepatotoxicity: is the FAERS signal real?

n=170 co-reports · PRR 18.1 · ROR 18.4

Nevirapine side-effect profile All assessments See in the full list

A written Bradford Hill assessment of one drug–event pair. The grade is a judgement about the signal, not a statement that this drug causes this event in any one person; FAERS counts are reports, not rates.

Causality: well established

Nevirapine ↔ Hepatotoxicity

n=170 co-reports · PRR 18.1 · ROR 18.4

Nevirapine, an HIV drug, carries a boxed warning for severe, sometimes fatal liver toxicity, including fulminant hepatitis that occurs most often in the first weeks of therapy and is more common in women with higher baseline liver enzymes. The reaction is genuinely drug-related, and it is why liver tests are monitored closely after starting the drug and why treatment is stopped at the first sign of hepatitis. The 170 co-reports (PRR 18.1) reflect both the real effect and the drug's use in HIV treatment, especially in resource-limited settings.

Regulatory basis: nevirapine prescribing information (boxed warning for severe hepatotoxicity; liver monitoring after initiation).

Bradford Hill viewpoint	Status	Note
Temporality (necessary)	met	Liver injury typically appears in the first weeks of therapy
Strength	met	PRR 18 on a modest co-report count
Consistency	met	Reproduced across HIV cohorts
Specificity	met	A recognised nevirapine effect, strongest early in treatment
Biological gradient	partial	Higher in women and with higher baseline liver enzymes
Plausibility	met	Immune-mediated and direct hepatocellular injury are proposed
Coherence	met	Coheres with the boxed warning and early liver monitoring
Experiment	partial	Dechallenge (withdrawal) is essential and can be life-saving; no randomized trial
Analogy	met	Analogous to hepatotoxicity from other antiretrovirals (nevirapine-class)

This page's own qualitative read, not an automated/citation-gated assessment.

✗ No ClinicalTrials.gov results-posting trial in the top search hits for nevirapine captured hepatotoxicity as a coded event; the severe early hepatitis is identified through the boxed-warning evidence base and HIV cohorts rather than a single trial AE table.