How Long Does Dulcolax Take to Start Working? - GoodRx (2024)

Making trips to the bathroom not as regularly as you’d like? Or maybe the situation’s more urgent, and you’re looking for a fast solution to what feels like a rush-hour traffic jam inside your intestines. Yeah, we’re talking about constipation. And every year Americans spend millions on over-the-counter (OTC) laxatives to treat it.

When treating constipation, experts suggest increasing your fiber and water intake as the first step. But what if you’ve already tried this without success, or you need to treat your constipation as soon as possible? The next step is often trying an OTC laxative like Dulcolax. But what type is right for you, and how long does it take for Dulcolax to work? Below, we’ll have the answers to these and more common questions about Dulcolax.

1. What dosage forms does Dulcolax come in?

Dulcolax contains one of three ingredients: bisacodyl, magnesium hydroxide, or docusate sodium. They all work in different ways to get things moving.

Bisacodyl

Bisacodyl is a stimulant laxative. It works by making the muscles in your intestines contract, which helps food move through faster. Dulcolax tablets and suppositories contain bisacodyl.

Magnesium hydroxide

Magnesium hydroxide is a saline laxative. It works by pulling extra water into your intestines. This both softens your stool and makes it larger, which helps it move through your body. Dulcolax liquid products and soft chews contain this ingredient.

Docusate sodium

Dulcolax stool softeners contain docusate sodium. As the name implies, it’s a stool softener — not a laxative. It works by making it easier for water and fats to mix into your stool, which helps soften things up. Docusate does not make you go to the bathroom; it only makes hard stool softer and easier to pass.

2. How long does it take Dulcolax to work?

The time it takes Dulcolax to start working depends on the type you take. And, naturally, how quickly a product can provide constipation relief will be a factor in which one you purchase. So we’ve made a table of Dulcolax products ranked from fastest to slowest to help you decide:

Fast relief

Dulcolax suppositories work the fastest — within 15 to 60 minutes. Suppositories are a dosage form that needs to be inserted into the rectum (anus) to work. To use, unwrap the suppository and insert it pointed-end first. It’s best to choose this option when you’ll be at home, close to your bathroom.

Magnesium hydroxide is the second-fastest option. Most people can expect relief within 30 minutes to 6 hours after taking it. It can be taken as a single dose at bedtime or you can divide up the dose over the course of one day. Because magnesium hydroxide pulls extra water into the intestines, staying hydrated is important. You’ll need to drink a full glass of liquid (like water or juice) with each dose.

Overnight relief

Next on the list are bisacodyl tablets, which work in about 6 to 12 hours. If you take bisacodyl tablets at bedtime, you can usually expect a bowel movement the next morning.

Gradual relief

Last, but not least, is docusate sodium. Remember that docusate sodium only softens the stool, which can help prevent straining during a bowel movement. It takes about 12 to 72 hours before you can expect your stool to feel softer. It’s also important to stay hydrated when taking stool softeners to help them work.

3. When does Dulcolax stop working?

Most laxatives work as they travel through your digestive system. So once they start to take effect, the results will quickly wear off as they move through your gut. Stool softeners linger a little longer in your intestines, so their effects can last up to a full day.

Bisacodyl tablets can cause the muscles in your intestines to contract for several hours once they start to work. So their effects may last a little longer than other laxative forms of Dulcolax.

If you take a laxative and it doesn’t work, or stops working after time, be sure to let your healthcare provider know. You could be overusing the laxative, or you may have a blockage in your bowels that’s preventing the laxative from working.

4. What are the side effects of Dulcolax?

Side effects will vary depending on the type of Dulcolax you take. But in general, they’re usually mild. Diarrhea and upset stomach are the most common side effects of all forms of Dulcolax. Docusate has the fewest side effects and is usually well tolerated at standard doses.

Bisacodyl stimulates the muscles in your intestines, so it tends to cause cramping and stomach discomfort. And there’s some concern that taking stimulant laxatives regularly can make you dependent on them — although this hasn’t been proven.

Magnesium laxatives are often advertised as a “gentler” laxative, but they still have side effects to consider. They can mess with your electrolyte levels, so they’re not recommended for people with kidney or heart problems. This can also cause problems for healthy people who overuse magnesium laxatives. So be sure to speak with your healthcare provider before using magnesium laxatives for more than 1 week.

5. Can I take Dulcolax with my other medications?

Talk to your pharmacist or healthcare provider if you’re taking prescription medications and want to take Dulcolax. In general, it’s best to avoid taking laxatives (including suppositories) at the same time as other medications.

Laxatives can sometimes interfere with how your body absorbs medications and nutrients. Magnesium hydroxide will need to be taken at least 2 hours apart from other medications. And bisacodyl will need to be taken at least 1 hour apart from any antacids or dairy products.

Docusate, though, is the exception to the rule. You don’t need to worry about timing since it has no known drug interactions.

6. Which type of Dulcolax is right for me?

As far as which laxative is best for you to take, that’s usually based on your preferences and symptoms. Below is a summary table of the pros and cons to consider for each type of Dulcolax medication.

When should I see a healthcare provider?

OTC laxatives are designed for occasional use. Never take laxatives for a longer period of time or at a higher dose than directed. Also, you shouldn’t take a higher dose than recommended. And never combine different types of laxatives without guidance from a healthcare provider.

It’s time to check in with a healthcare provider if you:

• Need to take Dulcolax (any type) for longer than a week

• Have not had a bowel movement within the expected time after taking Dulcolax

• Have other symptoms, like nausea and vomiting

• Notice blood in your stool

If you’re not having any bowel movement despite taking laxatives, this could be a sign of an impacted bowel or another issue. This would need to be managed by your healthcare provider.