Educational only — not medical advice. If you’re in crisis or thinking about suicide: call or text 988 (U.S.) or your local emergency number. Support resources. Under construction and review—see the updates log.

trihexyphenidyl

Adjunctive therapy

Brand: Artane

Published 2025-12-23 · Last reviewed 2025-12-30 · 5 references

Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.

Print sheet Review evidence

At a glance

Class: Adjunctive therapy·Typical dose: Parkinsonism: labeling describes starting at 1 mg on day 1, then increasing by 2 mg increments at intervals of 3–5 days toward a typical daily total of 6–10 mg/day (label).·PK (metabolism / half-life): Contemporary labels for older anticholinergics may not provide detailed pharmacokinetic parameters; practical dosing is guided by clinical response and adverse effects (label/clinical).·LAI available: No

Class: Adjunctive therapy
Typical dose: Parkinsonism: labeling describes starting at 1 mg on day 1, then increasing by 2 mg increments at intervals of 3–5 days toward a typical daily total of 6–10 mg/day (label).
PK (metabolism / half-life): Contemporary labels for older anticholinergics may not provide detailed pharmacokinetic parameters; practical dosing is guided by clinical response and adverse effects (label/clinical).
LAI available: No

Quick answers

What is trihexyphenidyl?: Trihexyphenidyl (brand Artane; generics) is an anticholinergic antiparkinson agent. In psychiatric care it is commonly used to treat antipsychotic-induced Parkinsonism and acute Dystonia, and sometimes other medication-induced extrapyramidal reactions (label/clinical).
What is Artane?: Artane is a brand name for trihexyphenidyl.
What is Artane (trihexyphenidyl) used for?: Label indications include: Parkinsonism (label). Common use includes control of antipsychotic-induced extrapyramidal reactions (label/clinical).
What drug class is Artane (trihexyphenidyl)?: Anticholinergic.
What is the mechanism of action of Artane (trihexyphenidyl)?: Anticholinergic (antimuscarinic) antiparkinson agent used for parkinsonism and to manage extrapyramidal reactions to antipsychotics. It can improve drug-induced parkinsonism and acute dystonia, but does not treat tardive dyskinesia and may worsen it; anticholinergic adverse effects often limit use.
What strengths does Artane (trihexyphenidyl) come in?: Tablets: 2 mg and 5 mg (label).

General information

Trihexyphenidyl (brand Artane; generics) is an anticholinergic antiparkinson agent used for parkinsonism and commonly used in psychiatric care for antipsychotic-induced Parkinsonism and acute Dystonia (label/clinical).

Labeling states anticholinergics do not alleviate TD and may aggravate TD, even though parkinsonism and TD can coexist in patients receiving chronic antipsychotics (label).

Anticholinergic adverse effects (constipation, urinary retention, blurred vision, confusion) are often the limiting factor, particularly in older adults and in patients with cognitive vulnerability (label/clinical).

For antipsychotic-induced parkinsonism, reviews emphasize assessing whether antipsychotic dose reduction or switching is feasible before relying on chronic anticholinergic therapy (Wisidagama 2021/clinical).

The trihexyphenidyl compare view, evidence feed, and print page support EPS counseling and regimen review.

U.S. approvals

Parkinsonism

Formulations & strengths

Tablets: 2 mg and 5 mg (label).

Generic availability

Available as generic; brand name Artane is widely recognized.

Trihexyphenidyl is often used as a targeted symptomatic agent rather than a chronic default. When possible, reducing the causative antipsychotic exposure and limiting anticholinergic burden are emphasized, particularly in older adults (clinical).

View labelExact

Mechanism of action

Refer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.

Antimuscarinic (anticholinergic) agent that reduces cholinergic tone in basal ganglia and can improve parkinsonism symptoms (mechanism/class).

Antimuscarinic (anticholinergic) antiparkinson agent.

Metabolism & pharmacokinetics

Contemporary labels for older anticholinergics may not provide detailed pharmacokinetic parameters; practical dosing is guided by clinical response and adverse effects (label/clinical).

Dosing & administration

Parkinsonism: labeling describes starting at 1 mg on day 1, then increasing by 2 mg increments at intervals of 3–5 days toward a typical daily total of 6–10 mg/day (label).
Antipsychotic-induced extrapyramidal reactions: dosing is individualized; labeling notes typical total daily dosing ranges between 5–15 mg/day, with some patients controlled on lower doses (label/clinical).
Dividing the total daily dose across meals can improve tolerability; high daily totals may be split with a bedtime dose as well (label/clinical).

Monitoring & labs

Anticholinergic adverse-effect monitoring (bowel function, urinary retention, blurry vision, dry mouth, tachycardia) (label/clinical).
Mental status monitoring (confusion/delirium), especially in older adults or when anticholinergic burden is high (clinical).
Screen for glaucoma risk and urinary obstruction symptoms when relevant (label/clinical).

If trihexyphenidyl is continued beyond acute symptom control, periodic reassessment of ongoing need helps avoid long-term anticholinergic burden that can worsen cognition and constipation (clinical).

Adverse effects

FDA boxed warnings

Common side effects (≥10%)

Dry mouth / blurry vision: Common anticholinergic effects; consider dose reduction if function is impaired (label/clinical).
Constipation: Common and potentially serious with high anticholinergic burden; monitor bowel function and avoid unnecessary anticholinergic stacking (label/clinical).
Urinary retention: Risk rises with age and prostate/urinary obstruction; reassess if urinary symptoms occur (label/clinical).
Confusion / delirium: Can occur, especially in older adults or with polypharmacy; reassess anticholinergic burden if cognition worsens (label/clinical).

Other notable effects

Labeling states anticholinergics do not alleviate TD and may aggravate it; trihexyphenidyl is used for parkinsonism symptoms rather than TD symptoms (label).
Heat intolerance and reduced sweating can occur; counsel about overheating risk (label).

Interactions

Additive anticholinergic burden occurs with TCAs, first-generation antihistamines, many antipsychotics (notably clozapine), and other anticholinergic agents; regimen review is often higher yield than adding more anticholinergic therapy (clinical).
Alcohol and sedatives can worsen dizziness and falls risk in the setting of anticholinergic load (clinical).
Anticholinergics can counteract cholinesterase inhibitors; co-use is generally avoided when dementia medications are present (clinical).

Other useful information

For antipsychotic-induced parkinsonism, reviews emphasize first evaluating dose reduction or antipsychotic switching feasibility, then using symptomatic agents when needed (Wisidagama 2021/clinical).
Anticholinergic burden has been associated with worse cognitive performance in schizophrenia-spectrum populations; minimizing unnecessary exposure is a common goal (Georgiou 2021/clinical).
Anticholinergics can reduce EPS symptoms but can worsen constipation and cognition; periodic reassessment and taper attempts are often considered once symptoms stabilize, especially in older adults and polypharmacy settings (clinical).
Acute Dystonia management commonly uses anticholinergic treatment; follow-up often focuses on preventing recurrence and ensuring the primary antipsychotic regimen is adjusted appropriately (Raja 1998/clinical).

References

Related hubs:SMI toolkit·Support resources