Dosing & Uses
Dosage Forms & Strengths
tablets
- 2mg
- 5mg
elixir
- 0.4mg/mL
Parkinson Disease
Initial: 1 mg PO first day, then increase by 2 mg q3-5days until reach 6-10 mg/days
Maintenance: 5-15 mg/day PO divided q6-8hr
Use SR product once stabilized on regular release product; when used with levodopa, generally use 3-6 mg/day in divided doses
Do not crush SR product
Monitor: IOP
Parkinsonism
5-15 mg/day PO divided q6-8hr
Drug-induced Extrapyramidal Symptoms
5-15 mg/day PO divided q6-8hr
Safety and efficacy not established
Nonanticholinergic antiparkinson agents should be considered first when treating Parkinson Disease (Beers Criteria)
Not recommended for preventing extrapyramidal symptoms
Parkinsonism
5-15 mg/day PO divided q6-8hr
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Adverse Effects
>10%
Anticholinergic side effects (30-50%)
Rash
<1%
Suppurative parotitis
Hallucination
Paralytic ileus
Warnings
Contraindications
Hypersensitivity
Angle-closure glaucoma
Cardiovascular disease
Cautions
GI obstruction, urinary retention, myasthenia gravis, hypotension, BPH, hepatic/renal impairment
Pregnancy & Lactation
Pregnancy Category: C
Lactation: no data; may inhibit lactation
Pregnancy Categories
A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA:Information not available.
Pharmacology
Mechanism of Action
Trihexyphenidyl inhibits the parasympathetic nervous system and has a relaxing effect on smooth muscles
Pharmacokinetics
Half-Life elimination: 33 hr
Onset: 1 hr
Peak effects: 1.3 hr
Duration: 6-12 hr
Metabolism: Unknown
Excretion: Urine and bile
Images
Patient Handout
Formulary
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.
