Trihexyphenidyl Hydrochloride
Generic Details
Generic Name
Trihexyphenidyl Hydrochloride
Other Names
- Benzhexol Hydrochloride
Drug Class
- Anticholinergic
Chemical Formula
C20H31NO2.HCl
Molecular Weight
337.93 g/mol
Mechanism of Action
- Blocks the action of acetylcholine in the central nervous system
Indications
- Parkinson's disease
- Drug-induced extrapyramidal symptoms
- Acute dystonia
Common Dosage Forms
- Tablet
- Liquid solution
- Extended-release capsule
Typical Dosage
- 2-15 mg per day in divided doses
Pediatric Dosage
- Not established
Geriatric Dosage
- Lower starting dose may be needed due to increased sensitivity
Side Effects
- Dry mouth
- Blurred vision
- Urinary retention
- Constipation
- Confusion
Contraindications
- Glaucoma
- Obstructive uropathy
- Myasthenia gravis
Pregnancy Category
- Category C - Risk cannot be ruled out
Lactation Safety
- Use with caution; excretion in breast milk unknown
Drug Interactions
- MAO inhibitors
- Antihistamines
- Tricyclic antidepressants
Overdose Symptoms
- Hallucinations
- Delirium
- Convulsions
Antidote for Overdose
- Physostigmine
Storage Conditions
- Store at room temperature away from moisture and heat
Pharmacokinetics
- Absorption: Well absorbed from the gastrointestinal tract
- Distribution: Crosses the blood-brain barrier, widely distributed in the body
- Metabolism: Metabolized in the liver
- Excretion: Excreted mainly in the urine
Precautions
- Use with caution in patients with cardiac arrhythmias
- May exacerbate psychotic symptoms in patients with schizophrenia
Warnings
- May cause drowsiness and blurred vision; caution when driving or operating machinery
Others
- May improve tremors and muscle stiffness associated with Parkinson's disease