Nimodipine
Chemical
CCB → DIHYDROPYRIDINE → cerebral selective
Use
- Prevent & treat cerebral vasospasm (i.e. delayed cerebral ischaemia post-SAH)
- Migraine
Presentation
IV: 200mcg/mL
PO: 30mg tablets
Dose/Route
IV via CVC: 1mg/hr first hour → 2mg/hr for 5 – 14 days
PO: 60mg QID
MoA
Specificity for cerebral arterioles
↓
Prevent Ca2+ entry into L-type Ca2+ channels
↓
Electromechanical decoupling
↓
Relaxation of cerebral vascular smooth m.
↓
VD of cerebral vessels
PD
CVS: ↓SVR, ↓CO
CNS: ↑CBF 20%
- Negates ‘steal’ effect of SAH
- ↓M+M of these patients significantly
PK
A
OBA 20% 2° 1st pass
D
99% PPB, VD 2L/kg
M
Liver → demethylated + dehydrogenated → into INACTIVE pyridine analogue → further degradation
E
50% → renal excretion of metabolites
30% → faecal
t ½ B = 7hrs
*** Dose adjustment for liver impairment
Adverse Effects
- Flushing
- Headache
- Nausea
- ↓BP
- Abnormal LFTs