Chlorpromazine-induced decrease of red cell aggregability

Starting from the assumption that binding of chlorpromazine to the erythrocyte membrane might influence th rheology of these cells, the authors studied erythrocyte aggregability and deformability by means of a filtrability test in 42 neurotics and 16 patients with personality disorders, all males, aged 20 to 27 years, clinically healthy from the somatic view point. Determinations were carried out before and 30 min after a single i.m. dose of 1 mg/kg b.w. chlorpromazine (14 patients) and before and after a 5-day oral treatment with 3 mg/day haloperidol (11 patients) or 75 mg/day chlorpromazine (33 patients). Chlorpromazine induced a significant decrease of erythrocyte aggregability after 5 days of oral treatment (p less than 0.02) the effect being more marked in the patients with relatively high initial values (p less than 0.01). The mechanism of this phenomenon and its possible implications of ESR determination and in the therapy of occlusive vascular diseases are discussed.