Bisacodyl
- Class: Stimulant laxative
- Used for: constipation
- Say it: bis-uh-KOH-dil
- Forms: tablet, suppository
BISACODYL makes the bowel BUSY. It prods the wall into action and the stool is pushed along within hours.
A stimulant laxative drives peristalsis directly — fast, but crampy. Never give it when obstruction is possible: driving peristalsis against a blockage risks perforation.
Bisacodyl irritates the enteric nerves and drives peristalsis directly. That is why it works within hours and why it causes cramping — an osmotic laxative simply draws in water and waits.
Side effects
Common: stomach cramps, diarrhea, nausea
Serious: salt loss with overuse
Typical dose
5–10 mg at night orally, or a 10 mg suppository
Swallow tablets whole; the enteric coating is what gets them past the stomach. A suppository works in under an hour, tablets overnight.
Check yourself
Why is bisacodyl a poor choice for long-term constipation?
- It is intended for short-term use; an osmotic laxative is better for chronic treatment
- It is absorbed and damages the liver
- It causes dangerous potassium retention
- It only works if taken with food
Show answer
A. It is intended for short-term use; an osmotic laxative is better for chronic treatment
Stimulants act fast but cause cramping and are not meant to be taken nightly for years. Macrogol works by holding water in the stool, which suits long-term use far better.
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