This randomized, double-blind, controlled clinical trial in parallel group design demonstrated equivalent efficacy and tolerability of a hop-valerian preparation compared with a benzodiazepine preparation in patients suffering from sleep disorders according to DSM-IV criteria. Sleep quality, fitness and quality of life were determined by psychometric tests, psychopathologic scales and sleep-questionnaires at the beginning of the therapy, end of therapy (duration 2 weeks) and then 1 week after cessation of therapy. Patients' state of health (4-point scale) and medication tolerability (occurrence of adverse events) were documented. Using the following as parameters "Alphabetischer Durchstreichtest, Feinmotoriktest, Befindlichkeitsskala, Beschwerdeliste, Schlaffragebögen A and B" the differences between beginning and the end of the therapy were analyzed by simultaneous testing of the equality or superiority of the test preparation. The equivalence of both therapies according to sleep quality, fitness and quality of life was proven by a Mann-Whitney-Statistic of 0.50 with a lower boundary of the 95% confidence interval of 0.46. The patients' state of health improved during therapy while showing a deterioration after cessation with both preparations. Withdrawal symptoms, however, were documented with benzodiazepine. Only one adverse drug reaction was reported during this study, namely stomach complaints from both the test and reference medication. This study shows that the investigated hop-valerian preparation in the appropriate dose is a sensible alternative to benzodiazepine for the treatment of nonchronic and non-psychiatric sleep disorders.