Table 2. Antipsychotics with High or Low Selectivity for 5HT2A Receptors Relative to K_i Values at the D2 Receptor^a.

antipsychotic	KiD2/Ki	parkinsonism
(A) High Selectivity
amoxapine	33	low
clozapine	20	none
isoclozapine	6.7	catalepsy
risperidone	5.6	moderate
(B) Low Selectivity
olanzapine	2.2	moderate
quetiapine	1	none
thioridazine	0.8	low
chlorpromazine	0.6	yes
fluphenazine	0.14	yes
remoxipride	0.01	none
haloperidol	0.01	yes
raclopride	0.0004	yes

^aHuman-cloned 5HT2A in HEK293 cells (2–8 replicates) using 0.5 nM [³H]ketanserin (K_d = 0.55 nM). Adapted from refs (19), (20), and (26).