Comparative Cytochrome P450 In Vitro Inhibition by Atypical Antipsychotic Drugs
Table 1
Inhibitory effect of atypical antipsychotics on human liver microsomal CYP450 activity.
Antipsychotic
(%)
a (M)
bTherapeutic range (M)
cInhibitory potency
CYP1A2
Chlorpromazine
75.7
4.75
0.1–1
0.1158
CYP2D6
Levomepromazine
60.6
12.75
0.05–0.2
0.0098
Chlorpromazine
65.5
10.0
0.1–1
0.0550
Thioridazine
73.2
1.75
0.5–5
1.5714
CYP3A (1-hydroxylation)
Olanzapine
77.1
7.30
0.06–0.25
0.0212
Risperidone
70.0
10.35
0.04–0.15
0.0092
Levomepromazine
58.2
15.0
0.05–0.2
0.0083
CYP3A (4′-hydroxylation)
Olanzapine
58.8
21.1
0.06–0.25
0.0073
Haloperidol
55.4
1.38
0.01–0.04
0.0181
, maximum inhibition. estimates were obtained as described previously [17]. Retrieved from Kirchherr and Kühn-Velten [18]. Intrinsic inhibitory potency ([inhibitor]/), a measure of the potency of an inhibitor [19], was calculated relative to the mean of reported therapeutic concentrations [18].
