Classifications: anticholinergic; antimuscarinic; antispasmodic; antiparkinson agent; Therapeutic: antiparkinson
Pregnancy Category: C
5 mg tablets
Centrally acting synthetic anticholinergic agent with actions similar to those of atropine. Selectively blocks muscarinic
responses to acetylcholine (ACh), whether excitatory or inhibitory.
Diminishes the characteristic tremor of parkinsonism.
To relieve symptoms of parkinsonism syndrome (postencephalitic, arteriosclerotic, and idiopathic), and drug-induced extrapyramidal
Angle-closure glaucoma; pregnancy (category C), lactation. Safe use in children not established.
Hypotension; mental disorders; tachycardia; prostatic hypertrophy.
Route & Dosage
Adult: PO 2.5 mg t.i.d. p.c., may be gradually increased to 5 mg t.i.d. if tolerated with an additional 5 mg h.s. (max: 4560
Geriatric: PO Start with 2.5 mg 12 times/d
- Minimize adverse effects by administration of drug during or after meals.
- Store at 15°30° C (59°86° F) in tightly closed containers unless otherwise directed.
Adverse Effects (≥1%)Body as a Whole:
Flushing of skin, decreased sweating, headache, lightheadedness, dizziness, feeling of muscle weakness. Special Senses:
Blurred vision, mydriasis, photophobia. CV:
Palpitation, tachycardia, hypotension. GI: Dry mouth,
nausea, vomiting, epigastric distress, constipation
, paralytic ileus,
acute suppurative parotitis. Urogenital:
Urinary retention. Skin:
Skin eruptions (occasionally). CNS:
Mental confusion, psychotic-like symptoms
Additive adverse effects with anticholinergic agents
. Herbal: Betel nut
may induce extrapyramidal symptoms
3540 min. Duration:
Assessment & Drug Effects
- Monitor heart rate and rhythm and BP. Report palpitations, tachycardia, paradoxical bradycardia, or decreasing BP. Dosage
adjustment or discontinuation of drug may be indicated.
- Monitor therapeutic effectiveness. Generally more effective in controlling rigidity than tremors. Tremors may temporarily
appear to be exaggerated as rigidity is relieved, especially in patients with severe spasticity.
- Observe for and report symptoms of mental confusion, disorientation, agitation, and psychotic-like symptoms, particularly
in older adult patients who have low BP, to physician.
- Check for constipation and abdominal distention and provide information for preventing constipation.
Patient & Family Education
- Void before taking drug if urinary hesitancy or retention is a problem.
- Avoid potentially hazardous activities until response to drug is known because drug may cause blurred vision and dizziness.
- Relieve dry mouth by rinsing frequently with water, chewing sugarless gum or sucking hard candy, or increasing noncaloric
fluid intake. If these measures fail, a saliva substitute, available OTC, may help (e.g., Orex, Xero-Lube).
- Avoid alcohol and do not to take other CNS depressants unless otherwise advised by physician.