Antidepressants detected by the National Department of Forensic Chemistry in 5281 suicides in Sweden during the period 1992-1994 were related to data on usage expressed in person-years of exposure. Antidepressants were detected in 874 subjects (16.5%). In relation to their use, fluvoxamine, citalopram, moclobemide, mianserin and trimipramine were found more often than the reference drug, amitriptyline (i.e. over-risks). Toxic concentrations of antidepressants were detected in 232 subjects (4.4%). Most people committing suicide were not taking antidepressants immediately before their death, even though 40-85% may have been depressed. Undertreatment and therapeutic failure are the main problems with antidepressants, not the risk of using antidepressants in overdose. Comparisons of new antidepressants should focus on efficacy in relation to reference tricyclics. The huge increase in the use of antidepressants in Sweden since 1990-1991 has been paralleled by a significant decrease in suicide rates.