Dicyclomine%25252525252520hydrochloride

# Dicyclomine hydrochloride ## Overview Dicyclomine is an antispasmodic and anticholinergic agent that acts by direct relaxation of smooth muscle in the gastrointestinal tract and by blocking acetylcholine at parasympathetic sites. ## Primary Indications - Treatment of functional bowel/irritable bowel syndrome (IBS). ## Adult Dosing - **Oral:** 20 mg four times daily. - **Maintenance:** If efficacy is observed, may increase to 40 mg four times daily after one week. - **Max dose:** 160 mg/day (40 mg QID). Discontinue if efficacy is not achieved within 2 weeks. - **Intramuscular (IM):** 20 mg every 4 to 6 hours. (Note: IM route is for short-term use only; not for IV use). ## Pediatric Dosing - **Safety and efficacy have not been established** for pediatric patients. Use is generally avoided in infants due to reports of serious respiratory and CNS effects. ## Dose Adjustments - **Geriatric:** Start at the lowest possible dose (10 mg). Caution is advised due to increased risk of anticholinergic side effects (e.g., confusion, urinary retention, falls). - **Renal/Hepatic Impairment:** No specific guidelines; use with caution. ## Contraindications - Hypersensitivity to dicyclomine. - Infants < 6 months old. - Unstable cardiovascular status in acute hemorrhage. - Myasthenia gravis. - Obstructive GI disease (e.g., paralytic ileus, pyloroduodenal obstruction). - Severe ulcerative colitis or toxic megacolon. - Glaucoma. - Prostatic hypertrophy/urinary obstructive uropathy. ## Adverse Effects - **Common:** Xerostomia (dry mouth), dizziness, blurred vision, nausea, nervousness, somnolence, and constipation. - **Serious:** Tachycardia, palpitations, urinary retention, heatstroke (due to decreased sweating), and psychosis/confusion (especially in the elderly). ## Key Drug Interactions - **Anticholinergics:** Additive effects (e.g., antihistamines, tricyclic antidepressants, antipsychotics). - **Potassium Chloride:** Increased risk of GI mucosal ulceration from solid dosage forms due to delayed transit time. - **Digoxin:** Increased serum concentrations due to decreased GI motility. ## Monitoring - Monitor for improvement in IBS symptoms. - Assess for anticholinergic toxicity (tachycardia, confusion, urinary output). - Monitor for signs of heat exhaustion in hot, humid environments. ## Clinical Pearls - Administer dose 30 minutes before meals. - Taper gradually if used for prolonged periods to avoid withdrawal-like symptoms. - Significantly higher anticholinergic burden compared to other antispasmodics; consider safer alternatives (e.g., peppermint oil or antidiarrheals) in the elderly. - Dicyclomine should not be used to treat patients with undiagnosed abdominal pain or patients with pre-existing autonomic neuropathy. *** **Educational Disclaimer:** This information is for educational purposes only. Clinical practice protocols vary by institution. Always verify dosages, contraindications, and drug interactions against the most current FDA-labeled prescribing information (e.g., DailyMed) or institutional clinical decision support tools before prescribing or administering medication.