Nabilone has shown modest effectiveness in relieving fibromyalgia. A 2011 systematic review of cannabinoids for chronic pain determined there was evidence of safety and modest efficacy for some conditions.
In one study of current daily users of cannabis, oral nabilone at 4, 6, and 8 mg produced sustained and dose-dependent mood elevation and psychomotor slowing comparable to 10 or 20 mg oral dronabinol (THC). Nabilone had a slower onset of peak action and a greater dose-dependence of effects, which the investigators attributed to greater bioavailability. 
Nabilone is sometimes used for nightmares in post-traumatic stress disorder, but there have not been studies longer than nine weeks, so effects of longer-term use are not known. Nabilone has also been used for medication overuse headache.
Nabilone was originally developed by Eli Lilly and Company; Lilly received FDA approval in 1985 to market it, but withdrew that approval in 1989 for commercial reasons.Valeant Pharmaceuticals acquired the rights from Lilly in 2004. Valeant tried and failed to get the medication approved in 2005 and then succeeded in 2006.
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