Dulcolax

What is Dulcolax?

Dulcolax is a stimulant laxative used to treat short-term constipation. It contains bisacodyl, which contracts and relaxes the muscles to move food and decreases water reabsorption.^[1] It’s only recommended if you’ve tried natural ways to help your constipation, such as increasing your fibre intake, drinking more water or using other laxatives such as Fybogel and Lactulose.

How does Dulcolax work?

Dulcolax is a gastro-resistant tablet, meaning it’s resistant to being broken down in the stomach and small intestines. Instead, it reaches the colon where bisacodyl, the active ingredient, is converted into the more active form, BHPM. ^[1]

BHPM stimulates the muscles in the gut to contract and relax, so food can move through more easily and efficiently. This process is known as peristalsis.

Additionally, you need something called ‘healthy colon motility’ to be able to have efficient bowel movements. BHPM can improve colon motility by:

• Reducing water absorption which increases the water content in the stool, making it softer to pass through.
• Stimulating the colonic motor activity and intestinal secretion (release of enzymes and substances that help with digestion). This reduces the time it takes for food to be excreted (aka transit time) and further softens the stool. ^[1]

Collectively, the combined actions of bisacodyl make it an effective laxative treatment for constipation.

What forms of Dulcolax are there?

Dulcolax comes in three forms; tablet, suppository or liquid. Dulcolax tablets and suppositories contain the same active ingredient, whereas the liquid form contains sodium picosulfate.

The time it takes for each Dulcolax form to work varies. Dulcolax tablets and liquid can take around 6-12 hours to work. Dulcolax suppositories can work in 10-45 minutes, so it’s best to stay near a toilet in case you have some urgency.

The doses for each form also vary. Dulcolax tablets come in 5mg, Dulcolax suppositories come in 5mg and 10mg doses and Dulcolax liquid is available in 5mg/5ml.

How to take Dulcolax

Always take the tablet as recommended by your clinician.

When you take Dulcolax:

• Take the tablets at night. It takes approximately 6-12 hours for Dulcolax to have a laxative effect. By taking it at night, you’ll be able to pass stool when you wake up in the morning.
• Swallow the tablets whole. Don’t chew or crush them, as this will reduce the laxative effects.
• Don’t have milk, antacids or proton pump inhibitors (anything that reduces stomach acid), one hour before or after taking it. These can all prevent Dulcolax from working properly.

Your clinician will decide the dosage and length of the treatment. If you haven’t taken Dulcolax before, you might start with one tablet.

You’ll take Dulcolax until your bowel movements are normal again. But if you’ve been taking Dulcolax every day for five days, stop taking it and contact your doctor. There may be an underlying cause of your constipation.

How long does Dulcolax take to work?

Bisacodyl tablets can take up to 12 hours to work. This is why it’s best to take them at night so that you can relieve yourself in the morning. You may need to take the tablets for more than one day, as it can take several days for bowel movements to return to normal. But it’s important not to take Dulcolax for any longer than five days.

What should I do if I make a mistake when taking Dulcolax?

If you take too many Dulcolax tablets, or take them for more than five days, go to your local casualty or talk to your doctor. Taking too many can cause:

• an imbalance of fluid and salts in the body, affecting your muscles;
• low levels of potassium in the blood, making you tired, dizzy and weak; or:
• dehydration, making you feel thirsty and faint.

If you experience any of the above, go to the hospital straight away.