Dicyclomine

Nursing pharmacology study reference (NCLEX-style monograph). Numeric values are standard teaching ranges for study and must be verified against current manufacturer labeling before clinical use. This is educational content, not prescribing guidance.

Dicyclomine (brand name Bentyl) — Antispasmodic; Anticholinergic.

Identification

• Therapeutic class: Antispasmodic.
• Pharmacologic class: Anticholinergic.

Pharmacology

• Mechanism of action: Relaxes GI smooth muscle by blocking acetylcholine.
• Onset / peak / duration: Onset 1 to 2 hours; duration about 4 hours.
• Half-life / therapeutic level: Half-life about 1.8 hours initially; no routine level.

Clinical use

• Indications: Irritable bowel syndrome, functional GI spasm.
• Usual dose, route, frequency: 20 mg PO four times daily; IM available short term.
• Maximum dose / adjustments: Max about 160 mg/day; caution in elderly.

Safety

• Contraindications: Glaucoma, urinary or GI obstruction, myasthenia gravis, severe ulcerative colitis, infants.
• Black box warning: None.
• Interactions: Other anticholinergics, antihistamines (additive effects).
• Pregnancy / lactation: Use with caution.
• High-alert: No.

Adverse effects

• Common side effects: Dry mouth, blurred vision, constipation, urinary hesitancy, dizziness.
• Serious effects to report: Confusion, severe constipation, urinary retention.
• Antidote / reversal: Supportive care; physostigmine for severe toxicity.

Nursing process

• Assessment before administration: Glaucoma, urinary and GI status.
• Interventions during therapy: Monitor anticholinergic effects, especially in elderly.
• Monitor: Bowel and bladder function, vision.
• Evaluation / expected outcome: Reduced GI spasm.

Patient teaching

• Patient teaching: Expect dry mouth; use sugar-free candy; rise slowly.
• Notify provider if: Trouble urinating, confusion, eye pain.
• Administration tips: Before meals.