Nonprescription laxatives for constipation: Use with caution

If you've ever been constipated, you may have tried nonprescription laxatives. A number of factors can disrupt the bowels and cause constipation. These include diet, fluid intake, physical activity and several medicines.

Many different types of laxatives are available without a prescription. They may be safe and effective to treat constipation once in a while. But it's very important to read the label carefully and use them as directed. Overuse of laxatives has been linked to serious health conditions. And you could become dependent on them for a bowel movement.

Call your healthcare team immediately if you have:

  • Severe stomach cramps or pain.
  • Unexplained changes in bowel patterns.
  • Severe diarrhea.
  • Bloody stools or rectal bleeding.
  • Constipation that lasts longer than seven days even with laxative use.
  • Weakness or unusual tiredness.
  • Dizziness.

Before trying laxatives

How often you have a bowel movement can vary. You might have as many as three bowel movements a day or as few as three a week. If you are having fewer bowel movements than usual, you might be constipated. Also, constipation may involve stools that are difficult to pass because they're hard, dry or small.

Before turning to laxatives, try these lifestyle changes to help with constipation:

  • Eat fiber-rich foods. These include wheat bran, fresh fruits and vegetables, and oats. The average adult should get 25 to 31 grams of fiber per day.
  • Drink plenty of fluids daily. Try to drink about 8 to 10 glasses of caffeine-free and alcohol-free fluids throughout the day. A glass is 8 ounces.
  • Exercise regularly.

Lifestyle improvements relieve constipation for many people. But if constipation continues after making these changes, your next choice may be a mild laxative.

How laxatives relieve constipation

Laxatives work in different ways. How well each laxative type works varies from person to person. In general, fiber supplements are the gentlest on your body. These also are called bulk-forming laxatives. Metamucil and Citrucel fall into this category. Here are some examples of different laxatives. Even though many laxatives are available without a prescription, it's best to talk to your healthcare team first. They can help decide the safest kind of laxative for you.

Type of laxative (brand examples) How they work Side effects
Oral osmotics (Phillips' Milk of Magnesia, MiraLAX, Magnesium Hydroxide, Polyethylene glycol) Draw water into the colon to allow easier passage of stool Bloating, cramping, diarrhea, nausea, gas, increased thirst
Oral bulk formers (Benefiber, Citrucel, FiberCon, Metamucil) Absorb water to form soft, bulky stool, prompting normal contraction of intestinal muscles Bloating, gas, cramping or increased constipation if not taken with enough water
Oral stool softeners (Colace, Surfak, Docusate Calcium) Add moisture to stool to soften stool, allowing strain-free bowel movements Electrolyte imbalance if used for a long time
Oral stimulants (Dulcolax, Senokot Bisacodyl, Senna/Sennosides) Trigger rhythmic contractions of intestinal muscles to eliminate stool Belching, cramping, diarrhea, nausea, urine discoloration with senna and cascara derivatives
Rectal suppositories (Dulcolax, Bisacodyl, Pedia-Lax) Trigger rhythmic contractions of intestinal muscles and soften stool Rectal irritation, diarrhea, cramping

Oral laxatives can change how your body absorbs some medicines and nutrients. After long-term use, some laxatives can lead to an electrolyte imbalance or other serious health issues. Electrolytes include calcium, chloride, potassium, magnesium and sodium. They regulate several body functions. An imbalance of electrolytes can cause heart rhythm changes, weakness, confusion and seizures.

Combination laxatives: Check labels carefully

Some products combine different types of laxatives, such as a stimulant and a stool softener. But combination products don't necessarily work better than single-ingredient products. Also, they may be more likely to cause side effects.

A single-ingredient laxative may work better for you. Read labels to make sure you know what you're taking and use with caution.

Risks of laxative use

  • Interaction with medicines. Your medical history and medicines you're taking may limit your laxative options. Laxatives can interact with many medicines including certain antibiotics, heart and bone medicines. Read labels carefully. If you're not sure whether a certain laxative is safe for you, ask a healthcare professional. Take the recommended dosage. Don't take more unless your doctor tells you otherwise.
  • Complicating conditions. Laxative use can be dangerous if constipation is caused by a serious condition. This includes a bowel blockage, also called an intestinal obstruction.
  • Dependency. Using laxatives too much for weeks or months can make constipation worse. This happens because they can decrease your colon's ability to contract.
  • Precautions for pregnant women and children. Don't give laxatives to children under age 6 without a healthcare professional's recommendation. If you're pregnant, ask your healthcare team before using laxatives. Bulk-forming laxatives and stool softeners are generally safe to use during pregnancy. But stimulant laxatives may be harmful.
  • Precautions for nursing mothers. If you've recently given birth, talk to a healthcare professional before using laxatives. Although they may be safe to use during breastfeeding, some ingredients may pass into breast milk. This may cause diarrhea in nursing infants.

Take laxatives with caution

Using laxatives incorrectly can cause serious health conditions. If you need laxatives to have a bowel movement, talk to your healthcare team. They will guide you on how to slowly withdraw from them. This should restore your colon's natural ability to contract.

Last Updated Jan 26, 2024


© 2024 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of Use