Most people can relieve constipation within a few hours to a few days using a combination of dietary changes, simple physical strategies, and over-the-counter options if needed. The approach that works fastest depends on how long you’ve been backed up and how uncomfortable you are right now.
Quick Relief: What Works Fastest
If you need to go now, your fastest options are suppositories or enemas, which typically produce a bowel movement within 15 minutes to one hour. These work by directly stimulating the rectum or softening stool right at the exit point. They’re available without a prescription at any pharmacy and are meant for occasional use.
A step down in speed, stimulant laxatives activate the nerves controlling your colon muscles, essentially forcing your colon into motion. These take about 6 to 12 hours, so taking one before bed often produces a morning result. Osmotic laxatives pull water into your colon to soften stool. The saline types (like milk of magnesia) can work in as little as 30 minutes, while others take one to three days. Polyethylene glycol (sold as MiraLAX) is one of the most widely used and falls in the slower end of that range.
Stool softeners increase the water and fat your stool absorbs, but they’re the gentlest and slowest option, taking 12 hours to three days. They work best for prevention rather than acute relief.
Use Your Body’s Built-In Triggers
Your body has a reflex called the gastrocolic reflex that you can use to your advantage. When food enters your stomach and stretches it, nerves automatically signal your colon muscles to start moving waste out. The colon responds with large, wave-like contractions. A bigger, higher-fat meal triggers a stronger response because it releases more digestive hormones. You can feel this movement start within minutes of eating, or up to about an hour later.
Coffee amplifies this effect. Caffeine independently stimulates colon contractions, so a cup of coffee with breakfast is one of the simplest things you can do to get things moving. Many people find their most reliable window for a bowel movement is within 30 to 60 minutes after their first meal of the day.
Fix Your Toilet Posture
The position you sit in on the toilet matters more than most people realize. When you sit upright on a standard toilet, a sling-shaped muscle called the puborectalis wraps around your rectum and chokes it at nearly a right angle. This is great for continence but terrible for pooping.
When you raise your knees above your hips (mimicking a squat), that muscle relaxes and the path from your rectum to the outside straightens to about 126 degrees. This reduces the amount of straining needed and lets stool pass more easily. You can get this effect by placing a footstool, a stack of books, or a “Squatty Potty” style platform under your feet while sitting on the toilet. Lean forward slightly with your elbows on your knees. The difference can be immediate.
Eat More Fiber (the Right Way)
Current dietary guidelines recommend 14 grams of fiber for every 1,000 calories you eat. For most adults, that works out to roughly 25 to 35 grams per day. If you’re constipated, there’s a good chance you’re falling short.
Prunes are one of the most effective high-fiber foods for constipation. In a randomized clinical trial, eating about 100 grams of dried prunes per day (roughly 10 to 12 prunes, split into two servings) provided 6 grams of fiber and outperformed psyllium, a common fiber supplement, for improving stool frequency. If whole prunes aren’t appealing, prune juice works too, though it has less fiber and more sugar.
Other good sources include beans, lentils, oats, chia seeds, raspberries, and pears. If you’re adding fiber supplements like psyllium (Metamucil) or methylcellulose (Citrucel), increase your intake gradually over a week or two. Jumping from low fiber to high fiber overnight often causes bloating and gas, which makes you feel worse before you feel better.
Drink Enough Water
Fiber works by absorbing water and swelling to create softer, bulkier stool. Without enough fluid, extra fiber can actually make constipation worse. One study of people with functional constipation who were already eating adequate fiber found that drinking about 2 liters of fluid per day increased bowel movement frequency and reduced the need for laxatives compared to drinking only 1 liter per day. Two liters is roughly eight 8-ounce glasses. Water, tea, coffee, and broth all count.
Move Your Body
Physical activity stimulates the natural contractions of your intestines. Even a 20-minute walk can help, especially after a meal when the gastrocolic reflex is already primed. You don’t need intense exercise. Gentle movement like walking, yoga, or stretching is often enough to nudge a sluggish colon into action. If you’ve been sedentary for days (during travel, illness, or a busy stretch at work), that alone can explain your constipation.
Do Probiotics Help?
The evidence is mixed. A large randomized trial tested a commonly promoted probiotic strain in 228 adults with functional constipation over 28 days. The probiotic performed no better than a placebo for the group overall. However, in a smaller subgroup of people with fewer than three bowel movements per week, combining the probiotic doses did improve frequency and reduce straining compared to placebo. Probiotics aren’t harmful, but they’re unlikely to be the thing that fixes constipation on their own. They’re better thought of as a possible supporting player, not the main solution.
When Constipation Signals Something Bigger
Occasional constipation from travel, stress, diet changes, or a new medication is normal and resolves with the strategies above. But certain symptoms alongside constipation warrant medical evaluation: blood in your stool, unintended weight loss of 10 pounds or more, a noticeable change in the shape or thickness of your stool, or constipation that starts suddenly in someone over 50. A family history of colon cancer or signs of iron deficiency anemia (unusual fatigue, pale skin) alongside constipation are also red flags. These don’t necessarily mean something serious is wrong, but they’re the patterns that prompt doctors to look more closely.