- Olanzapine it is a drug belongs to a group of medicines called atypical
antipsychotics. This drug’s efficacy in schizophrenia is mediated through a
combination of dopamine and serotonin type 2 (5HT2) antagonism.
- Olanzapine binds with high affinity to the following receptors:
serotonin 5HT2A/2C, 5HT6 , dopamine D1 - 4 , histamine H1 and adrenergic α1
- Olanzapine is an antagonist with moderate affinity binding for serotonin
5HT3 and muscarinic M1-5 .
- Olanzapine binds weakly to GABAA, BZD, and β-adrenergic receptors.
- Olanzapine is well absorbed and reaches peak concentrations in approxima-
tely 6 hours following an oral dose. Food does not affect the rate or extent of
- It is eliminated extensively by first pass metabolism, with approximately
40% of the dose metabolized before reaching the systemic circulation. Its
half-life ranges from 21 to 54 hours and apparent plasma clearance ranges
from 12 to 47 L/hr. It is 93% bound to plasma proteins over the concentra-
tion range of 7 to 1100ng / mL, binding primarily to albumin and α1-acid
glycoprotein. Approximately 57% and 30% of the dose was recovered in the
urine and feces, respectively.
- Direct glucuronidation and cytochrome P450 (CYP) mediated oxidation are
the primary metabolic pathways for Olanzapine.
- Clearance of Olanzapine may vary between individuals on the basis of
smoking status, gender and age.