Previous research has shown the repercussions of shiftwork for workers' sleep. The objective of the present work is to evaluate the impact of shiftwork on the length and quality of sleep among nurses and on the intake of psychotropic drugs. A cross-sectional epidemiological study was carried out in 606 female nurses and 367 male nurses selected at random from the public hospitals in the Valencian region. Information was collected by means of a questionnaire. Univariate and multivariate statistical analysis techniques were used. For both female and male nurses, shiftwork led to a reduction in the length of sleep (by 2 h in those permanently on night shifts and by 30 min in those on a rotating night shift system) and an alteration in the quality of sleep (difficulty in sleeping, intermittent sleep, early waking, etc. occurred 10% more frequently), but it did not lead to an increase in the consumption of psychotropic drugs.