For gas relief, an over-the-counter anti-gas medication containing simethicone is the fastest option, while constipation responds well to an osmotic laxative like polyethylene glycol (PEG 3350), which typically produces a bowel movement within one to three days. Since gas and constipation often show up together, you may need to address both at once with a combination of remedies, dietary changes, and hydration.
Simethicone for Gas Relief
Simethicone is the most widely available over-the-counter gas remedy, sold under brand names like Gas-X and Mylanta Gas. It works as a surfactant, lowering the surface tension of gas bubbles in your digestive tract so they merge together and pass more easily as burping or flatulence. It does not reduce how much gas your body produces. It simply helps the gas that’s already there move out faster.
The standard adult dose is 40 to 125 mg taken up to four times daily, typically after meals and at bedtime, with a maximum of 500 mg per day. Because simethicone is not absorbed into your bloodstream, it has very few side effects. In clinical trials, patients taking simethicone reported significant improvement in gas, bloating, pressure, and abdominal discomfort within five days compared to placebo.
Osmotic Laxatives for Constipation
Polyethylene glycol 3350 (sold as MiraLAX and store-brand equivalents) is one of the most commonly recommended options for constipation. It works by drawing water into the colon, softening stool and making it easier to pass. The standard adult dose is 17 grams dissolved in a beverage, taken once daily. Expect it to take anywhere from one to three days before you have a bowel movement, so this isn’t an instant fix.
Magnesium citrate is another osmotic laxative that works faster, typically producing a bowel movement within 30 minutes to 6 hours. It’s available as a liquid or powder you mix with water. Because it acts quickly and powerfully, it’s better suited for short-term, occasional use rather than a daily routine. Anyone with kidney disease should avoid magnesium citrate, since the kidneys are responsible for clearing excess magnesium from the body.
Stool Softeners: Gentler but Slower
Docusate sodium (the active ingredient in Colace) is a stool softener rather than a true laxative. It helps water and fats mix into stool so it passes more comfortably. In a head-to-head study comparing docusate to PEG 3350, about 67% of docusate patients had a bowel movement within 72 hours versus 71% in the PEG group, with no significant difference between them. The average time to a first bowel movement was roughly 49 hours for docusate and 45 hours for PEG. So stool softeners work, but they’re not meaningfully faster than an osmotic laxative. They’re a reasonable choice if your main issue is hard, uncomfortable stools rather than infrequent ones.
Stimulant Laxatives for Stubborn Cases
If osmotic laxatives and stool softeners haven’t worked after a few days, stimulant laxatives like bisacodyl (Dulcolax) or senna (Senokot) are a stronger option. These increase the muscular contractions of your intestines, physically pushing stool through. They’re effective but more likely to cause stomach cramps, discomfort, or faintness. Rectal bleeding is a rare but serious side effect that warrants stopping the medication immediately.
Stimulant laxatives are best reserved for occasional use. Relying on them regularly can make your bowels less responsive over time, creating a cycle where you feel like you need them to go at all.
Fiber: The Long-Term Fix
If gas and constipation are recurring problems, increasing your daily fiber intake is the single most effective lifestyle change. Adults need 22 to 34 grams of fiber per day depending on age and sex, and most people fall well short of that. Good sources include beans, lentils, whole grains, vegetables, fruits, and psyllium husk supplements (like Metamucil).
One important caveat: adding fiber too quickly can temporarily make gas worse. Start with small increases, maybe 5 extra grams per day, and build up over a couple of weeks. Your gut bacteria will adjust, and the gas usually subsides.
Fiber also works significantly better when paired with adequate water. In a two-month study of adults with chronic constipation, everyone ate about 25 grams of fiber daily, but the group that drank 2 liters of water per day had substantially greater improvements in stool frequency and less need for laxatives compared to the group drinking about 1 liter. The researchers concluded that 1.5 to 2 liters of water daily is the threshold where fiber’s benefits really kick in.
Probiotics That Actually Help
Not all probiotics are equal when it comes to constipation. A meta-analysis published in the World Journal of Gastroenterology found that two specific strains of Bifidobacterium lactis (HN019 and DN-173 010) produced meaningful reductions in the time it takes food to move through the digestive tract. Other tested strains showed small effects that weren’t statistically significant. The benefits were most pronounced in people who were already constipated, rather than in people with normal bowel habits.
You can find B. lactis HN019 in certain supplement brands and B. lactis DN-173 010 in some fermented dairy products. If you’re shopping for a probiotic specifically for constipation, check the label for one of these strains rather than grabbing a generic blend.
Peppermint Oil for Gas and Discomfort
Enteric-coated peppermint oil capsules are sometimes recommended for gas, bloating, and abdominal discomfort. The evidence is mixed. A randomized trial of 190 patients with irritable bowel syndrome found that peppermint oil didn’t meet its primary goals of reducing overall pain response or symptom relief compared to placebo. However, the small-intestinal-release formulation did produce statistically significant improvements in secondary measures of abdominal pain, discomfort, and symptom severity. So peppermint oil may offer modest relief for some people, but it’s not a reliable standalone treatment.
When Gas and Constipation Signal Something Else
Occasional gas and constipation are normal and respond well to the approaches above. But certain patterns point to something beyond a routine digestive slowdown. Blood in your stool, unintentional weight loss, and symptoms that wake you up at night are all red flags that warrant a medical evaluation. A sudden change in bowel habits after age 60 is another signal that deserves attention from a gastroenterologist. These symptoms don’t automatically mean something serious, but they overlap with conditions like inflammatory bowel disease and colorectal issues that benefit from early diagnosis.