Constipation usually doesn’t happen as a direct result of steroid use. But some of the long-term effects of steroid use on your body, such as lowered blood potassium levels, can cause constipation.

Steroids are a common treatment for conditions that cause inflammation, such as asthma and inflammatory bowel disease (IBD). You can expect some side effects when you use steroids, but they’re usually mild and don’t last long.

Read on to learn more about how using steroid medications can affect your bowel movements, other side effects of steroids, and what you can do to relieve and prevent constipation from steroid use.

There’s not a lot of evidence that steroids affect bowel movements or cause constipation.

But there’s a possible connection between one side effect of the corticosteroid medication prednisone — lowered blood potassium levels (hypokalemia) — and constipation.

Potassium is an electrolyte found in your bloodstream. Potassium has many benefits across your body, including drawing water into your stool as it passes through your colon. Having fluid in your stool makes it easier to move through the colon and out of your body.

When you take corticosteroids like prednisone, potassium levels in your blood can drop below normal levels. This makes it more difficult for water to be drawn into stool, leading to constipation over time.

Other steroids haven’t been clearly linked to constipation.

Some evidence shows that steroid medications can also affect the signals sent from your brain to your stomach and intestines to help muscles contract. This means stool might not move through your colon as smoothly, which could also cause constipation.

Many steroid medications can cause changes to how your intestinal muscles move — known as gastrointestinal motility — and result in uncomfortable symptoms.

Combined with lower potassium levels that make it less likely that your stool draws in water, you might find that longer periods pass between eating and having a bowel movement. If stool moves slowly through your colon, it can cause a bowel obstruction and keep other materials like gas from passing through, making you feel gassy.

Steroids like prednisone can also cause your body to retain more fluid, which can make you feel bloated.

Here are some of the most common short- and long-term side effects of steroid medications.

Short-term side effects

Short-term side effects can include:

Long-term side effects

Long-term side effects can include:

You may want to ask a doctor if you can stop taking steroid medications if they’re causing you to be constipated.

If you need to continue taking steroid medications, here are some other tips for relieving constipation:

  • Go to the bathroom as soon as you feel the need. The longer stool sits in your colon, the harder and more dried out it can become.
  • Raise your knees up when you sit down on a toilet. Use a stool if you have one.
  • Take your time when you’re on the toilet and try to relax. Don’t rush yourself or strain.
  • Try not to use laxatives or enemas unless nothing else works. Only use them for 2 weeks at a time so your body doesn’t become dependent on them.
  • Stop taking any other medications that might be causing constipation, such as diuretics that reduce fluid in your body.

Here are some tips to help prevent constipation when you’re taking steroid medications:

  • Drink at least 9–13 cups of water or other plain liquids every day.
  • Drink less alcohol and caffeine that could be dehydrating you and making constipation worse.
  • Eat foods with a lot of fiber, like raw vegetables or bran cereal.
  • Take probiotics to help promote the growth of healthy bacteria in your gut.
  • Exercise for about 150 minutes every week. Aerobic exercises like walking and swimming help maintain regular bowel movements.

It’s important to see a doctor right away if you have any of the following emergency symptoms of constipation:

Constipation isn’t a common symptom of steroid medications. But you might have constipation if your blood potassium levels drop from long-term use of prednisone.

Contact a doctor if you start feeling constipated or have other side effects while you’re taking steroid medications.