Dulcolax tablets contain bisacodyl, a stimulant laxative that makes the bowel muscles contract to move stool along. Knowing how long it takes helps you time it so it works when it suits you, not in the middle of your commute.
How long it takes
- Tablets: usually 6 to 12 hours. That’s why they’re normally taken at bedtime, for a bowel movement the next morning.
- Suppositories: much faster, usually 15 to 60 minutes.
How to take bisacodyl tablets
- Adults and children 12 and over: 1 to 3 tablets (5 to 15 mg) once a day. Start with the lowest dose.
- Children 6 to 11: 1 tablet (5 mg) once a day.
- Children under 6: ask a doctor.
- Swallow tablets whole with water. Don’t crush or chew them.
- Don’t take them within 1 hour of antacids, milk or dairy. These can dissolve the protective coating too early and cause stomach irritation and cramps.
Side effects
Stomach cramps, discomfort and diarrhoea are the most common. Taking the lowest dose that works reduces them. Stop and see a doctor if you have rectal bleeding or don’t have a bowel movement after using a laxative.
How long can you use it?
Don’t use bisacodyl for more than 7 days in a row unless a doctor advises it. Stimulant laxatives are meant for occasional constipation. If you need them regularly, see a doctor to look for the cause.
Check with a doctor first if you
- have stomach pain, nausea or vomiting
- notice a sudden change in bowel habits lasting more than 2 weeks
- are pregnant or breastfeeding
Try these too
Fibre, fluids and activity help prevent constipation coming back. See our guide to constipation relief: quick fixes and habits.
Shop Dulcolax (Bisacodyl).
More in our Digestive Health guide: all our articles and products on this topic in one place.
This article is for general information only and isn’t a substitute for advice from a doctor or pharmacist. Always read the label before using any medicine.
