Haloperidol
Chemical
Butyrophenone antipsychotic → first gen antipsychotic
Use
- Delirium & agitation in ICU
- Schizophrenia
- N&V
Presentation
Tablets, syrup solution (5mg/mL)
Dose
1 – 15mg (divided doses)
Route
PO/IV/IM
Onset
IM → 30 mins
PO → 60 mins
CMAX → 6hrs
MoA (mechanism)
- Central dopaminergic blockade
- Post synaptic GABA antagonism
PD
CNS
- ↓motor activity
- Anxiolysis
- ↑seizure threshold
- Indifference to external environment
CVS – ↓BP (some α1 antagonism)
GI – antiemesis (powerful) by ↑vomiting threshold @ CTZ
PK
A
OBA 60%
D
90% PPB
VD 9 – 20L/kg
M
Liver glucuronidation then reduction
(some) active metabolites
E
Metabolites via urine
15% faeces
t ½ B 10 – 45hrs
Adverse Effects
- Hypotension
- Abnormal LFTs
- GI & haematopoietic disturbances
- EXTRAPYRAMIDAL → NMS