The fastest way to trigger a bowel movement is a glycerin or bisacodyl suppository, which typically works within 15 to 30 minutes. If you’d rather not use a suppository, a combination of warm water, a change in sitting position, and abdominal massage can often get things moving in under an hour. For slightly less urgent situations, liquid magnesium citrate taken orally can produce results in as little as 30 minutes, though it sometimes takes up to six hours.
Suppositories: The Fastest Option
If you need results now, a glycerin suppository is the quickest over-the-counter option. It works by drawing water into the rectum and lubricating the stool, producing a bowel movement in 15 to 30 minutes for most people. You can find them at any pharmacy without a prescription.
Bisacodyl suppositories work on a similar timeline by stimulating the muscles in your lower intestine. Both types are meant for occasional use, not daily relief.
Liquid Magnesium Citrate
Magnesium citrate is a liquid you drink (usually mixed with water), and it works by pulling water into your intestines to soften stool and trigger contractions. Its onset ranges from 30 minutes to 6 hours, making it less predictable than a suppository but still one of the faster oral options. The standard adult dose is roughly 195 to 300 mL, always taken with a full glass of water to prevent dehydration. It tastes mildly citrusy and is sold in most drugstores in ready-to-drink bottles.
Change Your Sitting Position
Your body is actually better designed to poop in a squat than on a standard toilet. Squatting widens the angle between your rectum and anal canal, creating a straighter path for stool to pass. Research comparing the two positions found that people averaged 51 seconds to complete a bowel movement while squatting, compared to nearly two minutes on a regular-height toilet seat.
You don’t need to squat on the floor. A small footstool (about 7 to 9 inches tall) placed in front of your toilet lets you raise your knees above your hips, mimicking a squat. Lean slightly forward, relax your belly, and let gravity do more of the work. This single change can make a noticeable difference, especially if you feel like stool is “right there” but won’t come out.
Warm Liquids and Coffee
Drinking a large glass of warm water or a cup of hot coffee on an empty stomach can stimulate your colon’s natural contractions. Coffee is particularly effective because compounds in it (both caffeinated and decaf) increase activity in the colon within minutes of drinking it. This is why many people have a bowel movement shortly after their morning cup.
If coffee isn’t your thing, plain warm water with a squeeze of lemon works for many people. The key is volume and temperature: aim for at least 8 ounces, warm or hot, and drink it relatively quickly rather than sipping slowly.
Abdominal Massage
Massaging your abdomen in a clockwise direction follows the natural path of your colon and can help move stool along. A meta-analysis of studies on constipation found that abdominal massage consistently increased bowel movement frequency in adults. Start on your lower right side near your hip bone, press gently upward toward your ribs, across your upper belly, and down the left side. Repeat for 5 to 10 minutes. You can do this while sitting on the toilet. Combining the massage with the raised-knees position gives you the best chance of a quick result.
Prune Juice
Prune juice contains sorbitol, a natural sugar alcohol that draws water into the intestines the same way magnesium citrate does. For adults, half a cup (about 4 ounces) twice a day is a standard starting amount. Some people respond to a single 8-ounce glass in the morning. It’s not as fast as a suppository, but it’s one of the most reliable food-based options and typically works within a few hours.
Oral Stimulant Laxatives Are Slower
Senna (sold as Senokot and generics) is a popular stimulant laxative, but it takes about 8 hours to work when swallowed as a tablet or liquid. That makes it a better option to take before bed so you can go in the morning, not something that will help in the next hour. The same is true for oral bisacodyl tablets. If you’re looking for speed, the suppository version of bisacodyl is far faster than swallowing the pill.
Fiber Helps Prevent the Problem
Fiber won’t get you out of a jam right now, but it’s the most effective long-term fix. The recommended intake is 14 grams per 1,000 calories you eat, which works out to roughly 25 grams a day for most women and 30 to 34 grams for most men. Over 90% of women and 97% of men in the U.S. fall short of that target. Adding fiber-rich foods (beans, oats, berries, flaxseed) gradually over a couple of weeks, paired with plenty of water, makes constipation less likely to happen in the first place.
If you suddenly eat a lot of fiber without increasing your water intake, it can actually make constipation worse. Increase both together.
Signs Something More Serious Is Happening
Occasional constipation is common and usually harmless. But if you haven’t had a bowel movement for an extended period and you’re experiencing severe abdominal pain or significant bloating, that combination can signal an emergency like a bowel obstruction. Vomiting alongside constipation, blood in your stool, or unexplained weight loss also warrant urgent medical attention.