What is Bisacodyl used for?

Bisacodyl is evaluated for the following indications with varying evidence strength: Chronic constipation (evidence tier B), Weight loss (evidence tier F). See the full indication matrix with dosing and citations above on this page.

What are the side effects of Bisacodyl?

Common side effects of Bisacodyl (≥ 1 in 100): Abdominal cramping, Diarrhea, increased stool frequency, Nausea. See the Safety section for uncommon and serious reactions.

Who should not take Bisacodyl?

Bisacodyl is contraindicated in: Intestinal obstruction, perforation; Acute appendicitis, peritonitis; Severe dehydration; Acute inflammatory bowel disease; Age under 6 (oral 5 mg form). Full list in the Safety section.

Per 2023 and 2014, stimulant laxatives are second-line for chronic constipation in adults after baseline measures (adequate hydration, fiber, physical activity) and osmotic laxatives (PEG, lactulose). Bisacodyl 5–10 mg at bedtime. Efficacy confirmed by meta-analyses. Continuous use beyond 1–2 weeks is linked to hypokalemia and 'colonic conditioning' – the clinical significance of melanosis coli and dependence is now debated in guidelines, but long-term self-medication is not recommended.

Weight loss

Not recommended

Bisacodyl and other laxatives for weight loss are unsafe – they cause electrolyte disturbance, dehydration, acid-base imbalance, and iatrogenic 'lazy bowel' with long-term use. In patients with eating disorders, laxative abuse marks serious pathology requiring psychiatric and psychotherapeutic support. Apparent weight loss is water – not fat.

Sources

Timing and administration

Take at bedtime — effect at 6–12 hours in the morning. Swallow the tablet whole — the enteric coating prevents gastric irritation. Avoid milk, antacids, or PPIs within 1 hour — the coating dissolves in the stomach and causes nausea and cramping. Continuous use beyond 7–10 days without medical advice is not recommended. Constipation lasting over 2 weeks warrants evaluation.

Contraindications

Intestinal obstruction, perforation
Acute appendicitis, peritonitis
Severe dehydration
Acute inflammatory bowel disease
Age under 6 (oral 5 mg form)
Hypersensitivity

Serious adverse effects

Electrolyte disturbance (hypokalemia) with long-term use
Dehydration in elderly
Melanosis coli (benign, reversible)

Common adverse effects

Abdominal cramping
Diarrhea, increased stool frequency
Nausea

PregnancyFDA B

FDA categories were retired in 2015. In pregnant women with constipation, fiber and osmotic laxatives (PEG, lactulose) are first-line. Bisacodyl on strict indication only when others fail. May cause transient uterine cramping — avoid in patients at risk of preterm labor.

Breastfeeding

Minimal systemic absorption. Compatible with breastfeeding.

Calculate RID Full profile on NIH LactMed ↗

Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.

Bisacodyl

Mechanism of action

Indications

Chronic constipation

Marketing claims without evidence base

Weight loss

Practical notes

Timing and administration

Check interaction with another drug

Official sources

Safety