Antidepressant poisoning deaths in New Zealand for 2001

To compare the rates of death per volume of drug dispensed for antidepressants in New Zealand.

Deaths from antidepressant poisonings were identified from the reports of coronial inquiries for New Zealand in 2001. Prescriptions for antidepressant medications were identified from the PharmHouse database from 1 January 2001 to 31 December 2001. The rates of deaths (95% CI) per prescription, tablet/capsule or defined daily dose were calculated for individual antidepressants and classes of antidepressant.

There were 200 poisoning deaths recorded in the database for New Zealand in 2001. Antidepressants were involved in 41 deaths, and death was attributed to an antidepressant in 23 cases. There were 5.52 (95% CI 3.85-7.68) deaths per 100 000 prescriptions for tricyclic antidepressants (TCAs) and 2.51 (1.57-3.79) deaths per 100 000 prescriptions for selective serotonin reuptake inhibitors (SSRIs). There was marked variability in rates of death per volume of drug dispensed between individual antidepressants.

SSRIs have lower rates of death per volume of drug dispensed than TCAs and there is also variation in these rates within these classes of drugs. Toxicity in overdose should be considered when prescribing antidepressants.