Core pharmacology

Class Group

Anti-emetic

Dopamine Antagonist

Legacy Cicm Level

Level 3

Introduction

Phenothiazine D2-antagonist

Mechanism of action

1. Central and peripheral D2
2. Other effects:
- Inhibition of 5-HT3
Anti-H1 effects

Physiological effects

CVS- reversible ECG changes, QTc prolongation, alpha blockade

CNS- neurolepsis

GIT- LOS tone increased

Adverse Effects Toxicity

1. NMS
2. EPS
3. Sedation
4. Hyperprolactinaemia
5. QTc prolongation
Anticholinergic

Absorption

10% oral bioavailability

Protein binding

99% PB

Volume of distribution

Vd 20L/Kg

Metabolism

CYP3A4 and 2D6

Half-life

T1/2 6-8 hours