Non-fatal overdose of duloxetine in combination with other antidepressants and benzodiazepines

Abstract

The pharmaco-toxicological profile of duloxetine, a novel SNRI antidepressant, is still not completely known; in particular, intoxication cases have been scarcely studied. Here a duloxetine overdose case, in combination with other antidepressants and benzodiazepines, is reported and the chemical–clinical correlations discussed; this is probably the first detailed report of such a case. The patient referred to have ingested nine tablets of Cymbalta^® (more than 500 mg of duloxetine) and high amounts of four other drugs (venlafaxine, trazodone, sertraline and clonazepam). The patient was dozy and confused and some electrolyte imbalances were found. After gastrolavage, toxicological analyses revealed high plasma levels of duloxetine (384 ng/ml) and low levels of the other supposedly involved drugs. The overdose resulted to be not fatal and the outcome was relatively benign, also thanks to the fast emergency assistance. This case suggests that clinicians should be alerted to the possibility of toxic effects caused by simultaneous overdoses of duloxetine and other antidepressants and that caution should be used when prescribing more than one of these drugs to patients at risk of suicide.

• Duloxetine
• overdose
• depression
• HPLC-UV analysis
• plasma levels