Benzodiazepine Hypnotic — Long-acting Pregnancy: Do not use during pregnancy, especially during the first and last trimesters, unless there are compelling reasons. Nitrazepam crosses the placental barrier (feto-maternal plasma concentration ratio about 0.6 in early and about 0.9 in late pregnancy); data in pregnant women are limited and there have been isolated reports of very large doses causing congenital abnormalities in humans; animal studies have shown reproductive toxicity. If prescribed to a woman of childbearing potential, she should be warned to contact her physician regarding discontinuance if she intends to become or suspects that she is pregnant. Administration in the last trimester or during labour has been reported to produce irregularities in the foetal heart rate, and hypotonia, poor sucking, hypothermia and moderate respiratory depression in the neonate; infants born to mothers who took benzodiazepines chronically in the latter stages of pregnancy may have developed physical dependence and may be at risk of withdrawal symptoms postnatally. Breast-feeding: benzodiazepines are found in breast milk and use in breast-feeding mothers should be avoided. Fertility: human data are not available; nitrazepam impaired spermatogenesis in male mice and rats.

Nitrazepam

Brand names: Mogadon

Nitrazepam is a long-acting benzodiazepine used for the short-term treatment of insomnia.

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: Adults: 5 mg before retiring; this dose may, if necessary, be increased to 10 mg

Route: Oral

Frequency: Once daily, taken just before going to bed

Max: 10 mg in adults. ELDERLY OR DEBILITATED PATIENTS: doses should not exceed half those normally recommended; if organic brain changes are present the dosage should not exceed 5 mg

Source: UK SPC (eMC) for Mogadon 5 mg Tablets, §4.2 (https://www.medicines.org.uk/emc/product/3901/smpc). DURATION: treatment should be as short as possible and should be started with the lowest recommended dose; the maximum dose should not be exceeded. Generally the duration of treatment varies from a few days to two weeks, with a maximum of four weeks including the tapering-off process. Treatment should, if possible, be on an intermittent basis and dosage adjusted on an individual basis. Patients who have taken benzodiazepines for a prolonged time may require a longer period during which doses are reduced, and specialist help may be appropriate. In certain cases extension beyond the maximum treatment period may be necessary; if so, it should not take place without re-evaluation of the patient's status. DEPENDENCE STRATEGY: prior to starting treatment, a discussion should be held with patients to put in place a strategy for ending treatment in order to minimise the risk of dependence, addiction and drug withdrawal syndrome. Therapy should NOT be stopped abruptly — the dose should be tapered off. It may be useful to inform the patient at the start that treatment will be of limited duration and to explain precisely how the dosage will be decreased, and to make the patient aware of the possibility of rebound phenomena. ACCUMULATION: for long-acting benzodiazepines, the patient should be checked regularly at the start of treatment in order to decrease, if necessary, the dose or frequency of administration to prevent overdose due to accumulation. OTHER POPULATIONS: in patients with chronic pulmonary insufficiency and in patients with chronic renal or hepatic disease, the dosage may need to be reduced. PAEDIATRIC: Mogadon tablets are CONTRAINDICATED for use in children — no paediatric dose is stated and none should be inferred; verify any under-18 use against a children's formulary. OPIOIDS (§4.4): concomitant use of nitrazepam and opioids may result in sedation, respiratory depression, coma and death; concomitant prescribing should be reserved for patients for whom alternative treatment options are not possible, at the lowest effective dose and for the shortest duration, with close follow-up for respiratory depression and sedation. §4.4 was truncated at the source-fetch limit and §4.5 was not retrieved in this bundle — verify the complete interactions section. No openFDA/US label was retrieved for this drug. METHOD OF ADMINISTRATION: oral.

Dose adjustments

Renal

The elderly and patients with impaired renal and/or hepatic function are particularly susceptible to the adverse effects — doses should not exceed half those normally recommended. In patients with chronic renal or hepatic disease the dosage may need to be reduced.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to benzodiazepines, to nitrazepam or to any of the excipients
Severe respiratory insufficiency
Use in children (including short-term treatment of insomnia in children and juveniles)
Phobic or obsessional states; chronic psychosis
Myasthenia gravis
Sleep apnoea syndrome
Severe hepatic insufficiency

Side effects

Common: drowsiness, reduced alertness, headache, dizziness, fatigue, ataxia
Common: numbed emotions, confusional state, depression (pre-existing depression may be unmasked)
Common: muscle weakness (the myorelaxant effect carries a risk of falls and consequently fractures in the elderly); diplopia
Rare: vertigo, dysarthria, hypotension, abdominal discomfort, nausea, urinary retention, skin rashes, visual impairment, libido disorder
Frequency not known: physical and psychological dependence (even at therapeutic doses) and withdrawal syndrome with mood changes, anxiety and restlessness; drug abuse; agitation, aggression, delusion, anger, nightmare, hallucination, psychotic disorder, delirium, cognitive impairment; anterograde amnesia; respiratory depression; jaundice; anaphylactic reaction and angioedema; Stevens-Johnson syndrome and erythema multiforme

Interactions

Opioids — concomitant use may result in sedation, respiratory depression, coma and death; reserve for patients with no alternative options, use the lowest effective dose for the shortest duration and monitor closely (§4.4)
Other centrally-depressant drugs — the elderly are particularly sensitive to the effects of centrally-depressant drugs (§4.8). NOTE: §4.5 was not retrieved in this bundle; the full interactions section must be checked before publication

Clinical monograph

How it works

It potentiates the inhibitory neurotransmitter GABA at the GABA-A receptor, enhancing chloride channel opening to produce sedative, hypnotic and anxiolytic effects.

Prescribing in practice

Benzodiazepines should be prescribed for the shortest possible time because of the risk of tolerance, dependence and withdrawal, and nitrazepam's long half-life predisposes to next-day sedation and accumulation, especially in older people.
There is additive central nervous system and respiratory depression with alcohol and other sedatives, including opioids.
Avoid abrupt discontinuation after regular use, as this can precipitate a withdrawal syndrome; withdraw gradually.

Monitoring

Review the continued need for treatment regularly and monitor for daytime drowsiness, falls and signs of dependence.

Counselling the patient

This medicine can cause drowsiness the next day; take care when driving or operating machinery.
Avoid alcohol while taking nitrazepam.
Do not stop suddenly after taking it regularly; your prescriber will help you reduce it gradually.

Evidence & guidelines

Guidance from NICE and the MHRA emphasises short-term, lowest-effective use of hypnotic benzodiazepines such as nitrazepam because of dependence and next-day impairment.

Reference: NICE NG215 (Insomnia); Beers Criteria; STOPP/START Criteria; 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