SSRI SAFETY IN OVERDOSE

Background: The morbidity and mortality caused by tricyclic antidepres sant (TCA) overdose are well recognized. Among newer antidepressants, the selective serotonin reuptake inhibitors (SSRIs) are thought to be safer in overdose. This study was designed to describe the signs, symp toms, and mortality associated with SSRI overdose. Method: English-lan guage articles identified through MEDLINE (1985 through 1997), and cas e reports from the American Association of Poison Control Centers (AAP CC) (1987 through 1996) and United States Food and Drug Administration (FDA) adverse event database (through 1997) that describe findings of fatal and nonfatal overdoses involving SSRIs done or in combination w ith other ingestants were reviewed. Results: SSRI antidepressants are rarely fatal in overdose when taken alone. During the 10 years that SS RI antidepressants have been marketed, there have been remarkably few fatal overdoses reported in the literature or to the AAPCC or FDA invo lving ingestion only of an SSRI. Moderate overdoses (up to 30 times th e common daily dose) are associated with minor or no symptoms, while i ngestions of greater amounts typically result in drowsiness, tremor, n ausea, and vomiting. At very high doses (> 75 times the common daily d ose), more serious adverse events, including seizures, electrocardiogr am (ECG) changes, and decreased consciousness may occur. SSRI overdose s in combination with alcohol or other drugs are associated with incre ased toxicity, and almost all fatalities involving SSRIs have involved coingestion of other substances. Conclusion: The SSRI antidepressants are far safer than the TCAs in overdose. There is no apparent differe nce among SSRIs with respect to overdose safety.