Treating primary insomnia - the efficacy of valerian and hops.

OBJECTIVE: To evaluate the efficacy of valerian and hops in the treatment of primary insomnia. METHODS: The AMED and MEDLINE databases were searched for primary sources of literature published between 1950 and 2009, using keywords: herbal medicine, medicinal plants, herbal, Valeriana officinalis, valerian, Humulus lupulus, hops, sleep, insomnia. Studies were included if they evaluated the efficacy of valerian or hops in improving primary insomnia in adults: sixteen studies met the inclusion criteria. Twelve of these found that the use of valerian, on its own, or in combination with hops, is associated with improvements in some sleep parameters (eg. sleep latency and quality of sleep). However, these results need to be interpreted cautiously as there were significant differences in design between the studies. CONCLUSION: Further randomised, double blind, placebo controlled trials are needed before such herbal treatments can be confidently recommended for the treatment of primary insomnia.