Nimetazepam (marketed under brand name Erimin and Lavol) is an intermediate-acting hypnotic drug which is a benzodiazepine derivative.

Outside of Japan, Erimin is available in much of East and Southeast Asia and was widely prescribed for the short-term treatment of severe insomnia in patients who have difficulty falling asleep or maintaining sleep.

Nimetazepam was widely prescribed in the 1980s and 1990s, particularly in Japan, Malaysia, Brunei, the Philippines, Thailand, Indonesia, Hong Kong and Singapore.

It is also still used in the most severe and debilitating cases of insomnia in an inpatient setting or in short term outpatient treatment.

Although prescriptions for nimetazepam have decreased, abuse of the drug is still significant in Brunei, Singapore, Malaysia, and the Philippines.

The active ingredient, adulterant, major diluent, and dyes make up the chemical characteristics of a tablet.

Nimetazepam has a particular reputation in South East Asia for recreational use, at around USD 7 per tab, and is particularly popular among persons addicted to amphetamines or opioids.

[7] Nimetazepam also has withdrawal suppression effect and lower drug seeking versus nitrazepam in rhesus monkey (Macaca Mulatta).

[13] The illegal possession or consumption of Nimetazepam is punishable by up to 10 years of imprisonment, a fine of 20,000 Singapore dollars, or both.

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".

[15] 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.

[17] In a rat study nimetazepam showed slight enlargement of the liver and adrenals and atrophy of the testes and ovaries were found in high dose groups of both drugs at the 4th and 12th week, however, in histopathological examination, there were no change in the liver, adrenals and ovaries.