Self-poisoning is a common way of killing oneself, especially among women. Because suicide is linked to depression, and antidepressants are often easily available, antidepressants are involved in around 25% of all poisoning suicides in the U.K. and 20-30% of non-fatal overdoses. It is therefore important to know if certain kinds of antidepressants are riskier than others. A team of researchers led by Keith Hawton from Oxford University compared numbers of prescriptions to numbers of deaths in cases of deaths by self-poisoning. They used data from six general hospitals in Oxford, Manchester and Derby between 2000 and 2006. The study found that older, tricyclic antidepressants were much riskier than the SNRI (Serotonin-Norepinephrine Reuptake Inhibitor) drug venlafaxine and the NaSSA (Noradrenergic and Specific Serotonin Antidepressant) drug mirtazapine. In turn these drugs were riskier than SSRIs (Serotonin Specific Reuptake Inhibitors). Among the tricyclic antidepressants dosulepin and doxepin were both riskier than amitriptyline while within the SSRIs citalopram was riskier than the other drugs.
Hawton, Keith ... [et al] - Toxicity of antidepressants: rates of suicide relative to prescribing and non-fatal overdose British Journal of Psychiatry May 2010, 196(5), 354-358