https://www.selleckchem.com/pr....oducts/scriptaid.htm
Positron emission tomography (PET) is a non-invasive imaging method to measure the molecule in vivo. PET imaging can evaluate the central nervous system drugs as target engagement in the human brain. For antipsychotic drugs, adequate dopamine D2 receptor occupancy ("therapeutic window" is reported to be from 65%-70% to 80% to achieve the antipsychotic effect without extrapyramidal symptoms. For antidepressants, the clinical threshold of serotonin transporter (5-HTT) occupancy is reported to be 70%-80% although the relation between th