Nimetazepam (marketed under brand name Erimin) is an intermediate-acting hypnotic drug which is a benzodiazepine derivative. It was first synthesized by a team at Hoffmann-La Roche in 1962. It possesses hypnotic, anxiolytic, sedative, and skeletal muscle relaxant properties. Nimetazepam is also an anticonvulsant. It is sold in 5 mg tablets known as Erimin. It is generally prescribed for the short-term treatment of severe insomnia in patients who have difficulty falling asleep or maintaining sleep.
Taken orally, nimetazepam has very good bioavailability with nearly 100% being absorbed from the gut. It is among the most rapidly absorbed and quickest acting oral benzodiazepines, and hypnotic effects are typically felt within 15–30 minutes after oral ingestion. The blood level decline of the parent drug was biphasic with the short half-life ranging from 0.5-0.7 hours and the terminal half-life from 8–26.5 hours (mean 17.25 hours).nitrazepam (Mogadon, Alodorm), to which it is partially metabolised. Nitrazepam has a long elimination half-life, so effects of repeated dosage tend to be cumulative.
It is the N-methylated analogue of
Nimetazepam has a reputation in Malaysia for being particularly subject to recreational use especially by persons addicted to amphetamines or opioids.
Nimetazepam is currently a Schedule IV drug under the international Convention on Psychotropic Substances of 1971.
In Singapore, nimetazepam is a class C drug under the Misuse of Drugs Act.
In Hong Kong, nimetazepam is regulated under Schedule 1 of Hong Kong's Chapter 134 Dangerous Drugs Ordinance. Nimetazepam can only be used legally by health professionals and for university research purposes. The substance can be given by pharmacists under a prescription. Anyone who supplies the substance without prescription can be fined $10000 (HKD). The penalty for trafficking or manufacturing the substance is a $5,000,000 (HKD) fine and life imprisonment. Possession of the substance for consumption without license from the Department of Health is illegal with a $1,000,000 (HKD) fine and/or 7 years of jail time.
In Victoria Australia, nimetazepam is regulated under Schedule 11 of "Drugs, Poisons and Controlled substances act 1981". It is deemed to fall under the category of "7-NITRO-1,4-BENZODIAZEPINES not included elsewhere in this Part". .
In a rat study Nimetazepam showed greater damage to the fetus, as did nitrazepam when compared against other benzodiazepines, all at a dosage of 100 mg/kg. Diazepam however showed relatively weak fetal toxicities. The same fetotoxicity of nitrazepam could not be observed in mice and is likely due to the particular metabolism of the drug in the rat.
US patent 3109843, Reeder, E. ; Sternbach, L. H., "Process for preparing 5-phenyl-1,2-dihydro-3H-1,4-benzodiazepines", issued 1963-11-05, assigned to Hoffmann-La Roche
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Chong, Y. K.; Kaprawi, M. M.; Chan, K. B. (2004). "The Quantitation of Nimetazepam in Erimin-5 Tablets and Powders by Reverse-Phase HPLC". Microgram Journal 2 (1–4): 27–33.
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- ^ "Misuse of drugs act, chapter 185".
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Saito, H.; Kobayashi, H.; Takeno, S.; Sakai, T. (1984). "Fetal toxicity of benzodiazepines in rats". Research communications in chemical pathology and pharmacology 46 (3): 437–447. PMID 6151222.
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- Org 25,435
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