Inhibits salivation and excessive respiratory secretions when given preoperatively. Reverses some of the secretory and vagal actions of cholinesterase inhibitors used to treat nondepolarizing neuromuscular blockade (cholinergic adjunct). Adjunctive management of peptic ulcer disease.
Inhibits the action of acetylcholine at postganglionic sites located in smooth muscle, secretory glands, and the CNS (antimuscarinic activity). Low doses decrease sweating, salivation, and respiratory secretions. Intermediate doses result in increased heart rate. Larger doses decrease GI and GU tract motility. Therapeutic Effects: Decreased GI and respiratory secretions.
Adverse Reactions/Side Effects
CNS: confusion, drowsiness. EENT: blurred vision, cycloplegia, dry eyes, mydriasis. CV: tachycardia, orthostatic hypotension, palpitations. GI: dry mouth, constipation. GU: urinary hesitancy, retention.
PHYSICAL THERAPY IMPLICATIONS
Examination and Evaluation
Assess heart rate, ECG, and heart sounds, especially during exercise (See Appendices G, H). Report a rapid heart rate (tachycardia) or signs of other arrhythmias, including palpitations, chest discomfort, shortness of breath, fainting, and fatigue/weakness.
Assess blood pressure (BP) when patient assumes a more upright position (lying to standing, sitting to standing, lying to sitting). Document orthostatic hypotension and contact physician when systolic BP falls >20 mm Hg or diastolic BP falls >10 mm Hg.
If used to treat peptic ulcer, monitor any changes in symptoms (i.e., decreased abdominal pain, improved appetite) to help document whether drug therapy is successful.
Because of the risk of arrhythmias and abnormal BP responses, use caution during aerobic exercise and other forms of therapeutic exercise. Assess exercise tolerance frequently (BP, heart rate, fatigue levels), and terminate exercise immediately if any untoward responses occur (See Appendix L).
To minimize orthostatic hypotension, patient should move slowly when assuming a more upright position.
Instruct patient and family/caregivers to report other troublesome side effects such as severe or prolonged drowsiness, confusion, vision problems, problems with urination, or GI problems (constipation, dry mouth).
Absorption: Incompletely absorbed (10%) after oral administration. Well absorbed after IM administration.
Distribution: Distribution not fully known. Does not significantly cross the blood-brain barrier or eye. Crosses the placenta.
Metabolism and Excretion: Eliminated primarily unchanged in the feces, via biliary excretion.
Half-life: 1.7 hr (0.6–4.6 hr).
TIME/ACTION PROFILE (anticholinergic effects)
|ROUTE ||ONSET ||PEAK ||DURATION |
|PO ||1 hr ||unknown ||8–12 hr |
|IM ||15–30 min ||30–45 min ||2–7 hr* |
|IV ||1–10 min ||unknown ||2–7 hr* |