Toxic dose
The toxic dose of a selective serotonin reuptake inhibitor (SSRI) varies by drug. Doses above 600 mg of citalopram and 300 mg of escitalopram have been associated with QT-interval prolongation and torsades de pointes. The toxic doses of other SSRIs are not well established, but ingestions of more than 50 times the ‘defined daily dose’1 have been reported without severe adverse effects.