(British Approved Name, US Adopted Name, rINN)
International Nonproprietary Names (INNs) in main languages (French, Latin, Russian, and Spanish):
Note. The following terms have been used as ’street names’ or slang names for various forms of nitrazepam: Don Moggies; Moogles; Nitro’s; The Don.
Pharmacopoeias. In China, Europe, International, and Japan.
European Pharmacopoeia, 6th ed. (Nitrazepam). A yellow, crystalline powder. Practically insoluble in water slightly soluble in alcohol. Protect from light.
Dependence and Withdrawal
As for Diazepam.
For the purpose of withdrawal regimens, 5 mg of nitrazepam may be considered equivalent to about 5 mg of diazepam.
Adverse Effects, Treatment, and Precautions
As for Diazepam.
Effects on the digestive system. Two children given nitrazepam as part of their antiepileptic therapy developed drooling, eating difficulty, and aspiration pneumonia symptoms improved in one patient when the dosage of nitrazepam was reduced. Manometric studies indicated that the onset of normal cricopharyngeal relaxation in swallowing was delayed in these patients until after hypopharyngeal contraction, resulting in impaired swallowing and spillover of material into the trachea. Other workers have found similar effects on swallowing and cricopharyngeal relaxation in children given nitrazepam. The deaths of 6 epileptic children under 5 years of age who were treated with nitrazepam have been reported. Three of the deaths were unexpected, and in view of the previous reports of swallowing difficulties and aspiration, it was recommended that the use of nitrazepam in young children be restricted to those in whom seizure control fails to improve with other anti epileptics. Another study also found an apparently increased risk of death, especially in young patients with intractable epilepsy, associated with nitrazepam therapy.
Porphyria. Nitrazepam has been associated with acute attacks of porphyria and is considered unsafe in porphyric patients.
As for Diazepam.
Nitrazepam is fairly readily absorbed from the gastrointestinal tract, although there is some individual variation. It is about 87% bound to plasma proteins. It crosses the blood-brain and the placental barriers and traces are found in breast milk. Nitrazepam is metabolised in the liver, mainly by nitroreduction followed by acetylation none of the metabolites possess significant activity. It is excreted in the urine in the form of its metabolites (free or conjugated) with only small amounts of a dose appearing unchanged. Up to about 20% of an oral dose is found in the faeces. Mean elimination half-lives of 24 to 30 hours have been reported.
Distribution into breast milk. A mean milk-to-plasma ratio of 0.27 was obtained after giving nitrazepam 5 mgfor5 nights to 9 puerperal women. The accumulation of nitrazepam in milk over the study period was similar to that in plasma.
Hepatic impairment. The pharmacokinetics of intravenous nitrazepam in 12 patients with cirrhosis of the liver has been compared with 9 healthy subjects aged 22 to 49 years and 8 healthy elderly subjects aged 67 to 76 years. The mean elimination half-life of nitrazepam was 26 hours in young and 3 8 hours in elderly subjects, the difference, which was not significant, being chiefly due to the greater volume of distribution in elderly subjects. Although there was also no significant difference between young and elderly subjects in percentage of unbound nitrazepam (13.0 and 13.9% respectively) there was a substantially higher unbound fraction in the patients with cirrhosis, the mean value being 18.9%, and clearance of unbound nitrazepam was reduced relative to healthy subjects.
Metabolism. Although the acetylation of the reduced metabolite of nitrazepam has been reported to be controlled by acetylator phenotype, no significant differences between either half-life or residual effects of nitrazepam were observed in slow and fast acety lators.
Uses and Administration
Nitrazepam is an intermediate-acting benzodiazepine with general properties similar to those of diazepam. It is used as a hypnotic in the short-term management of insomnia and is reported to act in 30 to 60 minutes to produce sleep lasting for 6 to 8 hours. Nitrazepam has also been used in epilepsy, notably for infantile spasms (see below).
The usual oral dose for insomnia is 5 mg at night, although 10 mg may be required in some patients. Elderly or debilitated patients should not be given more than half of the normal adult dose.
Epilepsy. Benzodiazepines are sometimes employed in the management of epilepsy, but their long-term use is limited by problems of sedation, dependence, and tolerance to the antiepileptic effects. Nitrazepam has perhaps been most useful in the treatment of infantile spasms (as for example in West’s syndrome) and the so-called infantile myoclonic seizures. The BNFC suggests that those aged from 1 month to 2 years may be given initial oral doses of 125 micrograms/kg twice daily, adjusted according to response over 2 to 3 weeks to 250 micrograms/kg twice daily (maximum 500 micrograms/kg, but not exceeding 5 mg, twice daily) the same total daily dose may also be given in 3 divided doses. There has been concern, however, over swallowing difficulties with subsequent aspiration and reports of unexpected death associated with the use of nitrazepam in young children (see Effects on the Digestive System under Adverse Effects, above).
British Pharmacopoeia 2008: Nitrazepam Oral Suspension; Nitrazepam Tablets.
Australia: Alodorm Nogadon
Brazil: Nitrapan Nitrazepol Sonebon
Canada: Nogadon Nitrazaclon
Denmark: Apodorm Nogadon Pacisyn
Germany: Dormalon Dormo-Puren Eatan N Imeson Nogadan Novanox Radedorm
Hong Kong: Nogadon
India: Hypnotex Nitavan Nitravet
Ireland: Nogadon Somnite
The Netherlands: Nogadon
Norway: Apodorm Nogadon
New Zealand: Insoma Nitrados
Russia: Eunoctin Nitrosun Radedorm
South Africa: Arem Nogadon Ormodon Paxaclorm
Singapore: Dima Nitrados
Sweden: Apodorm Nogadon
Thailand: Alodorm Nitrados
UK: Nogadon Remnos Somnite