The fastest way to relieve constipation is with a glycerin suppository or saline enema, which typically produces a bowel movement within 15 minutes to 1 hour. If you prefer something you can swallow, magnesium citrate liquid works within 30 minutes to 6 hours. Beyond those, several other options can help within the same day, and a few physical techniques may get things moving without any products at all.
Fastest Options: Suppositories and Enemas
Rectal treatments work the quickest because they bypass digestion entirely and act directly where the stool is stuck. A glycerin suppository lubricates the rectum and draws water into the stool, softening it so it can pass. A saline enema works similarly by flooding the lower bowel with fluid. Both typically trigger a bowel movement in 15 minutes to 1 hour.
A bisacodyl suppository is another rectal option. It stimulates the muscles of the intestinal wall to contract, with a similar onset of 20 to 60 minutes. If you’re dealing with hard, dry stool that feels “stuck” near the exit, rectal options are almost always the fastest route because they work right at the source of the problem.
Next Fastest: Magnesium Citrate
If you’d rather drink something than use a suppository, magnesium citrate is the quickest oral option. It’s a liquid you can buy at most pharmacies without a prescription. It works by pulling water into the intestines, which softens stool and stimulates the bowel to move. Most people have a bowel movement within 30 minutes to 6 hours.
Because it can cause a strong, sudden urge to go, it’s best to take it when you’ll be near a bathroom for the next several hours. Drink it chilled if the taste bothers you. Stay well hydrated afterward, since the mechanism that makes it work also pulls fluid from your body into your bowel.
Stimulant Laxatives: Slower but Reliable
Over-the-counter stimulant laxatives like senna and bisacodyl tablets are widely available, but they take longer than the options above. Senna works in 6 to 12 hours, and bisacodyl tablets take 10 to 12 hours. Both work by increasing the contractions of the intestinal muscles, physically pushing stool along. Because of that timeline, many people take them before bed so they can expect a bowel movement in the morning.
Stimulant laxatives are effective for occasional use, but they’re not ideal for daily or long-term reliance. If you find yourself reaching for them regularly, that’s a sign something else is going on with your digestion.
Osmotic Laxatives for Milder Constipation
Polyethylene glycol 3350 (sold as MiraLAX and store-brand versions) is one of the most commonly recommended laxatives, but it’s not fast. It typically takes 2 to 4 days to produce a bowel movement. It works by holding water in the stool to keep it soft, and it’s gentle enough for repeated use. If your constipation is mild or you’re looking for something to take regularly rather than for urgent relief, it’s a good choice. But if you need results today, choose one of the faster options above.
Physical Techniques That Help Right Now
Several things you can do with your own body may help move things along, especially when combined with one of the options above.
Abdominal massage: Lie on your back and use firm, deep pressure to massage your abdomen in a clockwise direction, following the path of the large intestine. Start at your lower right side near your hip, slide your hand up toward your ribs, across to the left side, and then down toward your lower left hip. Think of squeezing toothpaste through a tube. Continue for about two minutes. This follows the natural direction stool moves through the colon and can help encourage it along.
Positioning on the toilet: Raising your knees above your hips straightens the angle of the rectum, making it easier for stool to pass. You can do this by placing your feet on a low stool or a stack of books while sitting on the toilet. Lean forward slightly and let your belly relax. This position mimics a squat and reduces the amount of straining needed.
Warm liquids: Drinking a cup of warm water, coffee, or tea can stimulate the muscles in your digestive tract. Coffee is particularly effective for some people because it triggers contractions in the colon. Drinking it in the morning, when your body’s natural digestive reflexes are already active, may be enough to get things moving.
Prune Juice and Fiber
Prune juice is one of the most effective natural remedies for constipation. It’s high in fiber and sorbitol, a sugar alcohol that pulls water into the intestines much like an osmotic laxative. For adults, starting with four to eight ounces is a reasonable dose. Some people get results within a few hours, though it’s less predictable than a laxative.
Fiber supplements like psyllium husk can help soften stool and make it easier to pass, but they’re better for preventing constipation than for solving an acute episode quickly. Fiber works by absorbing water, increasing stool bulk and softness. If you add fiber, increase your water intake at the same time. Without enough fluid, extra fiber can actually make constipation worse.
Quick Reference by Speed
- 15 minutes to 1 hour: Glycerin suppository, saline enema, bisacodyl suppository
- 30 minutes to 6 hours: Magnesium citrate liquid
- A few hours (variable): Prune juice, warm coffee, abdominal massage
- 6 to 12 hours: Senna or bisacodyl tablets
- 2 to 4 days: Polyethylene glycol 3350
When Constipation Signals Something Serious
Most constipation is uncomfortable but harmless. However, if you experience sudden constipation with abdominal cramps and you cannot pass gas or stool at all, do not take a laxative. This combination can signal a bowel obstruction, which requires medical attention. Other signs that point to something beyond routine constipation include blood in the stool, very thin pencil-like stools, or chronic diarrhea that follows a long period of being constipated. These patterns warrant a conversation with a doctor rather than another dose of laxative.