Severe granulocytopenia secondary to chlorpromazine despite concurrent lithium treatment: a case report

Severe chlorpromazine-induced granulocytopenia where the white-cell count decreases to below 1,000/mm3 rarely occurs and lithium is known to cause leucocytosis. The use of lithium in the prevention of granulocytopenia induced by drugs is still controversial. This report describes a patient with bipolar disorder suffering from severe granulocytopenia and severe respiratory infection after receiving chlorpromazine 50 to 150 mg per day along with long term lithium therapy. Bone-marrow aspiration and biopsy revealed inhibited maturation of myeloid series in the promyelocyte stage. The findings were consistent with a drug-induced effect. White-cell count return to normal after the discontinuation of chlorpromazine. It was proved in this case that combined lithium therapy had no effect in preventing agranulocytosis induced by chlorpromazine.