From the Guidelines
Scopolamine is contraindicated in patients with glaucoma, gastrointestinal or urinary tract obstruction, myasthenia gravis, and hypersensitivity to anticholinergic medications, and precautions should be taken in elderly patients, those with liver or kidney dysfunction, and pregnant or breastfeeding women. The contraindications and precautions for scopolamine use are due to its mechanism of action as a muscarinic acetylcholine receptor antagonist, which can worsen certain conditions such as glaucoma by increasing intraocular pressure or exacerbate urinary retention in patients with prostatic hypertrophy 1.
Contraindications and Precautions
- Glaucoma (particularly narrow-angle glaucoma)
- Gastrointestinal or urinary tract obstruction
- Myasthenia gravis
- Hypersensitivity to anticholinergic medications
- Precautions in elderly patients, those with liver or kidney dysfunction, prostatic hypertrophy, tachycardia, and in patients with a history of seizures or psychosis
- Pregnant and breastfeeding women should use scopolamine only when clearly needed as safety hasn't been fully established
Alternative Medications
For motion sickness, alternative medications include:
- Dimenhydrinate (Dramamine) at 50-100mg every 4-6 hours
- Meclizine (Antivert) at 25-50mg once daily
- Promethazine (Phenergan) at 25mg every 4-6 hours
- Ondansetron (Zofran) at 4-8mg every 8 hours For postoperative nausea and vomiting, alternatives include:
- Ondansetron
- Granisetron (Kytril)
- Dolasetron (Anzemet)
- Metoclopramide (Reglan) 1
Mechanism of Action
Scopolamine works by blocking muscarinic acetylcholine receptors, which can worsen certain conditions like glaucoma by increasing intraocular pressure or exacerbate urinary retention in patients with prostatic hypertrophy 1.
Clinical Use
Scopolamine is used off-label in gastroparesis despite lack of supporting clinical studies, and its use in this context is not recommended due to the potential to slow gastric emptying 1.
From the Research
Scopolamine Contraindications
- Scopolamine is contraindicated in patients with narrow-angle glaucoma, as it can increase the risk of acute angle closure 2
- Patients with open-angle glaucoma can use scopolamine, but caution is advised, as it may affect intraocular pressure, pupil size, and accommodation, although a study found no statistically significant differences in intraocular pressure 2
- Other contraindications may include:
- Myasthenia gravis
- Obstructive uropathy
- Obstructive intestinal disease
- Ulcerative colitis
- Toxic megacolon
Precautions
- Scopolamine should be used with caution in patients with:
- Hepatic or renal impairment
- Cardiovascular disease
- Hypertension
- Prostatic hypertrophy
- Patients should be monitored for adverse effects, such as dry mouth, blurred vision, and urinary retention
Alternative Medications
- For patients with contraindications to scopolamine, alternative medications may include:
- Other anticholinergic agents, such as glycopyrrolate or atropine
- Antiemetic agents, such as metoclopramide or ondansetron
- Motion sickness medications, such as meclizine or dimenhydrinate