BackgroundIt is not clear if the frequency of deliberate self-harm (DSH) is the same in patients taking different pharmacological classes of antidepressant drugs.AimsTo compare the frequency of DSH in patients who had been prescribed a tricyclic antidepressant (TCA) or a selective serotonin reuptake inhibitor (SSRI) prior to the DSH event.MethodThis was a prospective study in 2776 consecutive DSH cases attending an accident and emergency department. The incidence of DSH in TCA-treated cases and SSRI-treated cases is expressed as number of DSH events per 10 000 prescriptions of each antidepressant.ResultsSignificantly more DSH events occurred following the prescription of an SSRI than that of a TCA (P < 0.001). The occurrence of DSH was highest with fluoxetine and lowest with amitriptyline.ConclusionsMerely prescribing safer-in-overdose antidepressants is unlikely to reduce the overall morbidity from DSH.