Antimuscarinic
Trihexyphenidyl hydrochloride
Brand names: Broflex
Adult dose
Dose: Initial 1mg PO OD, increase by 1-2mg every 3-5 days; usual 5-15mg/day in divided doses
Route: PO
Frequency: divided
Clinical pearls
- Drug-induced parkinsonism, dystonia
- Avoid in elderly (cognitive risk)
Contraindications
- Closed-angle glaucoma
- GI obstruction
- Urinary retention
- Myasthenia
- Tardive dyskinesia
Side effects
- Anticholinergic effects
- Confusion
- Sedation
- Tachycardia
- Urinary retention
Interactions
- Other antimuscarinics
- Levodopa
- CNS depressants
Reference: BNF; NICE NG71; https://bnf.nice.org.uk/drugs/trihexyphenidyl-hydrochloride/. Verify against your local formulary and the latest BNF before prescribing.
Related
Curated clinical cross-links plus same-class fallbacks.
Drugs
Pathways
- Acute Stroke / TIA Assessment · NICE NG128; RCP Stroke Guidelines 2023
- Status Epilepticus (Adults) · NICE CG137; ESEM guidelines; RCP Neurology Guidelines
- Suspected Subarachnoid Haemorrhage · NICE NG228; RCEM 2023; AHA/ASA 2023
- Adult Head Injury · NICE NG232 (2023)
- Bell's Palsy / Facial Nerve Palsy · ENT UK 2017; AAN
- Vertigo Workup · ENT UK; NICE CKS