Metoprolol
Chemical
Amide
Use
- Hypertension
- Post AMI
- Arrhythmias
Presentation
Tablets 25/50mg
Clear, colourless solution 1mg/mL
Dose
PO: 50 – 100mg BD
IV: 1 – 2mg boluses
Route
PO/IV
DoA
~4hrs
MoA
Competitive antagonist at β1 adrenoreceptors
Antagonises effects of catecholamines
PD
CVS:
- – VE CHRONO, – VE DROMO, – VE INOTROPY
- ↓myocardial O2 consumption
Metabolic: ↑TAGs, HDL, cholesterol
PK
A
50% OBA
D
10% PPB
M
Hepatic; 60% 1st pass metabolism
Inactive metabolites
E
Metabolites cleared in urine
<10% unchanged
t ½ B 6hrs
Adverse Effects
- Hypotension
- Bradycardia
- Masks hypoglycaemia