Drug therapy in women: "Off-label use"?

For many drugs, and this applies also for psychotropic drugs, sex-specific differences have been observed with regards to metabolism, adverse drug reactions and treatment response. Sex-specific differences have been demonstrated for clozapine, venlafaxine and fluvoxamine, where women exhibit higher plasma concentrations when compared to men. Hormone-dependent differences have also been shown for benzodiazepines, opioids and other sedatives/hypnotics. Men and women differ with regard to symptoms of depression and psychosis. This may - at least in part - explain differences in treatment response to different drug classes. The complex interaction between sex - or gender -and pharmacokinetics, pharmacodynamics and symptomatology is difficult to incorporate into the frame of randomized, controlled clinical trials. Sub-group analyses are often not adequately powered to confirm in a statistically correct way sex-specific differences. Off-label use means use of a drug outside its labelled indication. Psychotropic drugs on the German market are licensed for men and women, i.e., there is no off-label use when prescribing these drugs to women. However, many sex-differences with respect to psychopharmacotherapy are not yet well described, are not included in the design of most clinical trials and will therefore remain field for future research.