Types of Laxatives for Constipation

Fiber Supplements (Bulk Laxatives)

Fiber supplements soften the stool and stimulate a bowel movement. There are three basic types, each of which uses a different ingredient, such as psyllium, calcium polycarbophil, or methylcellulose. Here's a quick overview of them:

• Psyllium breaks down in the gut and becomes a food source for the good gut bacteria. It's used for a range of conditions, including IBS and diverticulosis (note that it's not recommended for diverticulitis). One big side effect: Psyllium can cause intestinal gas. 
• Calcium polycarbophil absorbs water in the digestive tract, making stools softer and bulkier. One drawback: It needs to be spaced out with other medications you're taking to ensure they're absorbed properly. 
• Methylcellulose, like polycarbophil, is plant-based and absorbs water in the gut. It's much less likely to cause intestinal gas than other fiber laxatives.

As with all laxatives, it is essential to drink plenty of fluids while using fiber supplements, or else they could actually worsen constipation.

Fiber supplements can interact with other medications and reduce or delay their effectiveness. Talk with your healthcare provider to ensure your medications are safe to take with a fiber supplement. Some medications that interact with these supplements include antidepressants, diabetes medications, and carbamazepine.

Osmotic Laxatives

Osmotic laxatives work by increasing the amount of fluid secreted within the intestines, resulting in softer and easier-to-pass stools. The three major osmotic laxatives are Miralax, lactulose, and milk of magnesia.

• Miralax, the brand name for polyethylene glycol PEG, acts similarly to fiber laxatives, as it draws water into the stool making it softer and easier to pass. It also stimulates more frequent bowel movements. Miralax has been found to cause less gas and bloating than other osmotic laxatives. 
• Lactulose increases the speed of intestinal contractions, stimulating bowel movements. 
• Milk of magnesia is no longer widely recommended because of the potential complications it may cause for patients with heart or kidney disease. There are safer and more effective options available.

Since osmotic laxatives draw water to the stool, overusing these medications may cause dehydration and electrolyte imbalances. Talk with your healthcare provider to ensure that these laxatives are right for you.

Stimulant Laxatives

Stimulant laxatives work by speeding up the movement of intestinal muscles, thus inducing a bowel movement. Many of the well-known products sold in your drugstore are stimulant laxatives, including Carters Little Pills, ExLax, and Dulcolax.

A stimulant laxative is generally recommended as a short-term treatment for constipation. There is research suggesting that long-term use of these laxatives may be harmful to the colon and increase the risk of cancer.

Check with your healthcare provider before using one of these products, as they can also interact with other over-the-counter and prescription medications. 

Herbal Stimulant Laxatives

There are many different herbs that have a reputation for having laxative effects. Aloe latex, cascara sagrada, frangula, rhubarb, and senna are all examples of herbal stimulant laxatives.

Herbal laxatives contain anthranoids, chemical compounds that stimulate the intestines, improving motility in the gut (in other words, keeping things moving along more quickly).

Herbal stimulant laxatives are not recommended for long-term use and can cause adverse gastrointestinal effects and other unpredictable reactions. Consult a medical professional before using herbal remedies. 

Stool Softeners

Stool softeners do just what the name suggests: soften the stool so it's easier to pass. They perform many of the same functions as a laxative, but technically aren't laxatives because they don't stimulate the gut. Most stool softeners contain a medication called docusate. Brand names include Colace, Doxinate, and Fleet Sof-Lax.

There are times when a stool softener may be a better option than a laxative to relieve constipation, especially if you have hemorrhoids or are pregnant (or both). You should consult your healthcare provider to determine which one is the best choice to help you get things moving again. 

Note that there is limited evidence to support the effectiveness of stool softeners. However, some people find stool softeners to be helpful, and because they are generally well-tolerated, they are a safe option to try.

Stool softeners are recommended for short-term use, but you can use them for longer periods if your healthcare provider gives you the green light.