The Best Types of Over the Counter Medications for Constipation

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Types of Constipation Medication

Not all over the counter medications for constipation are made equally. Each one works in a different way for the same purpose. However, since the reasons you’re constipated differ, you need to select a medicine that will directly tackle your symptoms, not just release stool.

Watch out for blood in your stool or a lack of improvement in constipation conditions if your symptoms still persist after a week.

Milk of Magnesia

Milk of magnesia, a popular over the counter constipation remedy, not only helps alleviate constipation, but it also can treat heartburn symptoms. This milky laxative comes in two forms – liquid and tablet – and is taken with a glass of water.

Milk of magnesia presumably works by using water sources in your body to attract liquid into the intestines and colon. This eases the depository process.

Taking this medication, especially in high doses or in extended use, may cause side effects including diarrhea, dehydration and a magnesium imbalance. Although this is a fairly tame drug, you might experience side effects such as bloating, flatulence, dizziness, difficulty breathing, rash or dry mouth.


Ex-Lax is another common constipation drug that comes in liquid and chewable tablet form. Unlike milk of magnesia, its effects actually cause the intestines to contract, which will force out the lodged stool.

You should also take Ex-Lax with water, even though its main purpose is not to draw water into the colon. Common side effects include burping, abdominal cramps and feeling faint or nauseous.


Colace is a stool softener. This over the counter medication employs liquids, like water and fat to relax hard stool and ease its movement through the intestines. This is not necessarily for regular constipation, but for when you feel the stool is very hard or rather dry.

Colace can be taken with food, but you do need to drink water and plenty of liquids while you’re on it. Colace is sometimes taken regularly (although you shouldn’t do so without a doctor’s orders), so be sure to take the recommended doses in the appropriate amounts each day.

Taking Colace may result in intestinal discomfort, cramps, vomiting or even appendicitis.


Dulcolax is one of the over the counter medications for constipation that is in suppository and tablet form. Unlike the previous medications, which sometimes cause stool movements within a few hours, a suppository gets things moving within minutes, so make sure you’re prepared for a stool movement shortly after taking Dulcolax.

Dulcolax suppositories are inserted directly into the rectum and dissolve on their own. Like Ex-Lax, Dulcolax is designed to cause the colon and intestines to contract for stool elimination.

Possible side effects are pretty much limited to the intestinal area, and not so much the stomach as the previous three. You might experience itching or irritation in your bowels, some abdominal discomfort or cramping.


Mayo Clinic: Over the Counter Laxatives for Constipation Colace