summary
Clozapine has a narrow therapeutic range. The threshold value for plasma concentrations is 350 μg/l. If plasma concentrations exceed that value, serious side-effects can occur. An increase in plasma concentrations can occur as a result of inflammatory processes which may or may not be caused by an infection. Two cases are discussed in which the plasma concentration of clozapine increased as a result of an inflammatory reaction and signs of intoxication were observed. These developments seemed to be due to cholecystitis and bacterial pneumonia respectively. The clinical presentation and pathophysiology are discussed in relation to inflammatory processes.