Is melatonin safe and effective in insomnia?
Q - Is melatonin safe? I am trying to avoid benzodiazepines for a patient with recurrent long-term sleep difficulties who has asked about melatonin, which is available from abroad via the internet. What do I say?
A - We don't have good evidence about melatonin's safety. But many millions have taken it short-term for jetlag and if there were problems I'm sure we would have heard by now.
Long-term administration is less common but even so has been pretty widespread in children and the elderly over the past seven or eight years. There are few reported side-effects, except headaches in children and a small number of children with epilepsy who had slightly increased incidence of seizures during melatonin administration.
The key question is: is this treatment likely to work in chronic insomnia?
There is very little evidence for this. Melatonin has been shown to improve symptoms of jetlag in normal adults, sleep phase disturbances in the non-sighted, and sleep disturbance in selected elderly patients, in children with Asperger's syndrome and with attention deficit hyperactivity disorder.
We prescribe melatonin occasionally, and our hospital pharmacy obtains it for us, so you could agree with your patient to prescribe a short course to see if it works before going to the internet, should you feel this was appropriate.
Dr Sue Wilson is honorary consultant and clinical electrophysiologist and
Dr David J Nutt is professor of psychopharmacology at the University of Bristol psychopharmacology unit in the School of Medical Sciences