Evidence category
Benzodiazepine efficacy, dependence, withdrawal, and long-term cognitive effects.
Benzodiazepines reduce anxiety symptoms versus placebo in short-term trials (SMD −0.58, low certainty), but physical dependence can develop within days to weeks (FDA FAERS: onset 'days to weeks,' withdrawal 'weeks to years'). Hip fracture risk is substantial (RR 1.52 overall, RR 2.40 new users). Dementia association (HR 1.60, observational) cannot establish causation. Among incident users, 39.4% → long-term use; 50% of patients dispensed oral benzodiazepines received them ≥2 months in 2018.