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Benzodiazepine Hypnotic — Long-acting Pregnancy: Avoid — neonatal respiratory depression, hypotonia, and withdrawal. Long half-life means neonatal effects may persist for days after delivery.

Nitrazepam

Brand names: Mogadon

Adult dose

Dose: Insomnia (short-term): 5mg at bedtime; elderly: 2.5mg at bedtime. Maximum treatment duration: 2–4 weeks.
Route: Oral
Frequency: Once nightly at bedtime
Max: 10mg OD (non-elderly adults — rarely required); 5mg OD (elderly)
Long-acting benzodiazepine hypnotic (half-life 16–38h) — significant next-day 'hangover' sedation and psychomotor impairment. Generally less preferred than temazepam (shorter-acting) due to greater residual sedation, falls risk in elderly, and cognitive impairment. Reserve for when shorter-acting hypnotics have failed. CD prescription not required (unlike temazepam) — schedulehas varied over time; check current legal status.

Paediatric dose

Route: Oral
Frequency: Once nightly
Max: Not applicable
Not licensed for insomnia in children. Used under specialist supervision in paediatric epilepsy (myoclonic, infantile spasms — see BNFc). Seek specialist paediatric neurology opinion for epilepsy use.

Dose adjustments

Renal

Use with caution in renal impairment — enhanced sedation and accumulation risk; reduce dose.

Hepatic

Avoid in severe hepatic impairment — accumulation risk; hepatic metabolism.

Clinical pearls

  • Antidote: flumazenil 200 micrograms IV, then 100 micrograms every 60 seconds (max 1mg) — note: nitrazepam half-life (16–38h) exceeds flumazenil half-life; repeat doses or infusion may be required
  • Falls risk in elderly: avoid nitrazepam in elderly — Beers Criteria and STOPP criteria explicitly list long-acting benzodiazepines as potentially inappropriate in older adults due to falls, cognitive impairment, and fractures
  • Hangover sedation: next-day impairment is significant — advise patients not to drive or operate machinery the morning after taking nitrazepam (impairment may persist 12–18h)
  • NICE NG215: temazepam preferred over nitrazepam for insomnia when benzodiazepine is needed — shorter half-life means less next-day impairment

Contraindications

  • Respiratory failure
  • Myasthenia gravis
  • Sleep apnoea syndrome
  • Severe hepatic impairment
  • Acute angle-closure glaucoma
  • Hypersensitivity to benzodiazepines

Side effects

  • Residual morning sedation (very common — long half-life)
  • Cognitive impairment, memory disturbance
  • Ataxia, falls (particularly in elderly)
  • Paradoxical agitation
  • Dependence and withdrawal
  • Respiratory depression (at higher doses or with CNS depressants)
  • Anterograde amnesia

Interactions

  • CNS depressants, opioids, alcohol — additive respiratory depression and sedation
  • CYP3A4 inhibitors — may increase nitrazepam levels
  • Rifampicin — reduces nitrazepam efficacy

Monitoring

  • Duration of use (strict 2–4 week limit)
  • Next-day sedation and driving safety
  • Falls assessment in elderly
  • Dependence symptoms

Reference: BNFc; BNF 90; NICE NG215 (Insomnia); Beers Criteria; STOPP/START Criteria. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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