BMC Neurology has published the results of the HYPNOS I clinical trial demonstrating the sedative action of the Cefaly medical device (http://www.ncbi.nlm.nih.gov/pubmed/22035386).

The results show, in a statistically highly significant manner using four clinical measurement methods, a pronounced reduction in vigilance induced by the action of the Cefaly(R) Hypnos medical device, by comparison to a placebo.

This sedative action on the central nervous system is observed after application for 12 minutes in 83% of individuals whose mean increase in tiredness was of 73%.

 The Cefaly is the first external cranial neurostimulation device. It is currently used to treat migraine and headaches and offers the best safety efficacy ratio by comparison to conventional prophylactic drugs. 

 Patients have reported a tendency to fall asleep when using the Cefaly, which has also been observed during tests or demonstrations. A clinical trial was undertaken to ascertain the veracity of these initial empirical observations. The sedative action demonstrated by the clinical trial is achieved only using certain specific neurostimulation parameters. 

 The Cefaly Hypnos version is available as a relaxation method for individuals in states of stress or hyperarousal. They say it should help certain insomniacs achieve sleep more readily. 

 Citation: Maxime Piquet, Costantino Balestra, Simona L Sava and Jean E Schoenen, 'Supraorbital transcutaneous neurostimulation has sedative effects in healthy subjects', BMC Neurology 2011, 11:135 doi:10.1186/1471-2377-11-135