How They Work and Differ From Other Laxatives
Osmoticlaxativesare medications used to treat or preventconstipation.
They draw extra water into your stool, making it softer and easier to pass.
Osmotic laxatives are available over the counter and by prescription.
Illustration by Jessica Olah, Verywell
Examples include Milk of Magnesia, lactulose, and polyethylene glycol (PEG).
How Osmotic Laxatives Work
Constipation triggers when stools are infrequent and hard to pass.
The stools will usually be hard and dry.
Osmotic laxatives can help relieve constipation by increasing the amount of fluid in the intestines.
This, in turn, softens stools and makes them easier to pass.
This is how osmotic laxatives work.
This is especially true of people who are don’t consume enough water.
This helps soften stools and makes them easier to pass.
The others are generally used for the treatment of occasional constipation.
Common Osmotic Laxatives
There are several common osmotic laxatives you might use if you have constipation.
Possible Side Effects
As with all drugs, osmotic laxatives can cause side effects.
Most are relatively mild and will resolve on their own within a couple of days.
The other osmotic laxatives are generally intended for short-term use.
Common side effects of osmotic laxatives include nausea, bloating, cramping, flatulence, and diarrhea.
The overuse of osmotic laxatives can lead to dehydration and other complications.
Summary
Osmotic laxatives can help treat or prevent constipation by drawing water into the colon.
This action helps soften stools and makes them easier to pass.
There are different types of osmotic laxatives that contain different active ingredients.
These include polyethylene glycol (PEG), lactulose, sorbitol, magnesium citrate, and magnesium hydroxides.
Osmotic laxatives can cause side effects like nausea, bloating, cramping, gas, and diarrhea.
The overuse of osmotic laxatives can cause dehydration and other potentially serious complications.
If you are thinking about using osmotic laxatives, be sure to follow the dosing instructions carefully.
To avoid complications, use a laxative only when needed.
It is a good idea to eat plenty of fiber-rich foods to optimize digestive health.
If you have chronic constipation, see your healthcare provider so that they can identify the underlying cause.
In some cases, the condition can be improved with diet, exercise, and increased fluid intake.
Others may require treatments that extend beyond the use of laxatives.
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