Scopolamine

INTRODUCTION

Indications

Transdermal: Prevention of motion sickness. Management of nausea and vomiting associated with opioid analgesia or general anesthesia/recovery from anesthesia. IM, IV, SC: Preoperatively to produce amnesia and to decrease salivation and excessive respiratory secretions.

Action

Inhibits the muscarinic activity of acetylcholine. Corrects the imbalance of acetylcholine and norepinephrine in the CNS, which may be responsible for motion sickness. Therapeutic Effects: Reduction of nausea and vomiting. Preoperative amnesia and decreased secretions.

Adverse Reactions/Side Effects

CNS: drowsiness, confusion. EENT: blurred vision, mydriasis, photophobia. CV: tachycardia, palpitations. GI: dry mouth, constipation. GU: urinary hesitancy, urinary retention. Derm: decreased sweating.

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.

• Be alert for decreased sweating and increased body temperature (hyperthermia), especially during exercise. Notify physician of a prolonged or persistent elevation in body temperature.

• Monitor any improvements in symptoms (nausea, vomiting, dizziness) to help document the effects of this drug.

• Monitor signs of urine retention (difficult urination, painful or distended abdomen). Excessive urinary retention may require dose adjustment by physician.

Interventions

• Because of the risk of arrhythmias and impaired thermoregulation, use caution during aerobic exercise and other forms of therapeutic exercise. Assess exercise tolerance frequently (blood pressure, heart rate, fatigue levels), and terminate exercise immediately if any untoward responses occur (See Appendix L).

Patient/Client-Related Instruction

• Instruct patient and family/caregivers to report other troublesome side effects such as severe or prolonged confusion, drowsiness, vision problems or GI problems (constipation, dry mouth).

Pharmacokinetics

Absorption: Well absorbed following IM, SC, and transdermal administration.

Distribution: Crosses the placenta and blood-brain barrier.

Metabolism and Excretion: Mostly metabolized by the liver.

Half-life: 8 hr.

Contraindications/Precautions

Contraindicated in: Hypersensitivity; Hypersensitivity to bromides (injection only); Angle-closure glaucoma; Acute hemorrhage; Tachycardia secondary to cardiac insufficiency or thyrotoxicosis.

Use Cautiously in: OB/Geri: Geriatric patients, infants, and children (↑ risk of adverse reactions); Possible intestinal obstruction; Prostatic hyperplasia; Chronic renal, hepatic, pulmonary, or cardiac disease; OB: Pregnancy or ...