Treatment of chronic depression with sulpiride: evidence of efficacy in placebo-controlled single case studies.

Systematic variation of treatment (alternating active drug and placebo in four treatment periods) in individual patients is proposed to collect preliminary evidence for a therapeutic effect of sulpiride in chronic depression; the ARIMA model is applied to evaluate the intervention effects of the tentatively effective treatment in single subjects. Ten single cases of chronic depression with a diagnosis of major depression or dysthymia were selected and seven of these provided evidence for beneficial effects of sulpiride with regard to treating the symptoms of depression and anxiety. However, the drug effects were intraindividually not always replicable. The results obtained with these single cases positively support the recommendation to perform regular randomized placebo-controlled trials with sulpiride in chronic depression. Simultaneously, these single case investigations reveal a lack of temporal stability of treatment response and inconsistencies of response with regard to different treatment targets in individual patients.