The actions of flupenthixol upon 5-hydroxytryptamine-induced aggregation and the uptake of 5-hydroxytryptamine and dopamine by human blood platelets.

The effects of the alpha- and beta-isomers of flupenthixol on 5-hydroxytryptamine (5-HT)-induced platelet aggregation and on 5-HT and dopamine uptake were investigated. Alpha-Flupenthixol was 185 times more potent than the beta-isomer as an inhibitor of platelet aggregation. In contrast both isomers were equipotent as inhibitors of uptake of 5-HT and dopamine. The data suggest that 5-HT-induced aggregation and uptake are separate processes.