Clinical melperone treatment blocks D2-dopamine receptors in the human brain as determined by PET

Positron emission tomography and 11-C-labelled raclopride was used to determine central D2-dopamine receptor occupancy in three melperone treated patients. Treatment with melperone in daily doses of 250 and 300 mg for 3 to 6 weeks, resulted in a receptor occupancy above 70%. Thus, clinical doses of melperone as we previously demonstrated for several classical neuroleptics cause a substantial D2-dopamine receptor blockade in the human brain in vivo.