Zopiclone Stats & Data

Zopiclone was developed by the French pharmaceutical company Rhône-Poulenc S.A. and first introduced to the market in 1986. Rhône-Poulenc has since become part of Sanofi, which remains the primary global manufacturer. Upon its release, zopiclone was marketed as offering improvements over benzodiazepines for treating insomnia, though subsequent meta-analyses have found it comparable to benzodiazepines across all assessed parameters. The substance remained unscheduled in the United States until April 4, 2005, when the Drug Enforcement Administration placed it under Schedule IV of the Controlled Substances Act, citing evidence of addictive properties similar to those of benzodiazepines. Zopiclone as marketed globally is a racemic mixture containing two stereoisomers, of which only one possesses pharmacological activity. In 2005, the same year as federal scheduling, the Massachusetts-based pharmaceutical company Sepracor began marketing the active stereoisomer separately as eszopiclone under the brand name Lunesta in the United States. This development effectively placed what functions as a generic medication in most countries under new patent protection within the American market. In France, zopiclone ranks among the ten most commonly obtained medications through fraudulent prescriptions, indicating significant diversion from legitimate pharmaceutical channels.

Forked from Subjective Effect Documentation by Josie Kins, September 2015. Via dose.wiki (CC0).

Zopiclone is generally thought to have a low toxicity relative to dose. However, it is potentially lethal when mixed with depressants like benzodiazepines, alcohol or opioids. When combined with one or several of these substances the already existing chance of a having a "black-out" is significantly increased, leaving the user with very little to no memory of the events that occurred whilst under the influence of zopiclone alone or combined with most other CNS depressants. Some users have reported taking zopiclone in combination with alcohol in an attempt to treat hangovers with varying degrees of success. It is strongly recommended that one use harm reduction practices when using this substance.

Effects aggregated from 23 experience reports (23 single-substance Erowid)

Each bar is the share of reports mentioning the effect; its whisker, and the band on the rows below, is the 95% interval: where the share could plausibly be with other reports of the same kind.

Also reported in combinations. In the 21 Zopiclone reports where another drug was taken too, 2 (9.5%) mention hospital, emergency services or an overdose, 0 (0.0%) a seizure and 3 (14.3%) psychosis. In the 23 single-substance reports: 4.3%, 0.0% and 0.0%. These are not in the figures above: they cannot be put down to Zopiclone alone, and a mention is not always something that happened to the writer.

Dose distribution from experience reports, one dose per report (the first listed). Doses above Q3 + 3×IQR, far above what people typically take, are left out of the median and range and listed under each route: most are real heavy doses or overdoses, not mistakes.

From 51 of 62 recorded dose entries: those that state a weight (mg, g or µg), in routes with at least five of them. Values above Q3 + 3×IQR, far above what people typically take, are left out; they can include real heavy doses and overdoses, not only mistakes.

Most co-occurring substances, as a share of all 44 reports filed under Zopiclone; whiskers are 95% intervals

Most common forms and preparations, as a share of the 30 reports that give one; whiskers are 95% intervals

Dose per kg of body weight, one dose per report (the first listed), from reports giving a weight of 30–250 kg. Doses above Q3 + 3×IQR, far above what people typically take, are left out of the median and range and listed under each route.

Redosing behavior across 35 reports