 Plasma, serum, or blood concentrations of paroxetine may be measured to monitor therapeutic administration, confirm a diagnosis of poisoning in hospitalized patients or to aid in the medicolegal investigation of fatalities.Plasma paroxetine concentrations are generally in a range of 40–400 μg/L in persons receiving daily therapeutic doses and 200–2,000 μg/L in poisoned patients.Postmortem blood levels have ranged from 1–4 mg/L in acute lethal overdose situations.