What is osmotic diarrhea?
Diarrhea is a common condition with many types, one of which is osmotic diarrhea.
Osmotic diarrhea occurs when too many solutes — the components of the food you eat — stay in your intestine and water can’t be absorbed properly. This excess water causes your bowel movements to be loose or more liquid than solid.
Osmotic diarrhea is similar to another type called secretory diarrhea.
Osmotic diarrhea occurs when you eat substances that can’t be absorbed. Secretory diarrhea occurs when your body secretes electrolytes into your intestine. This causes water to build up. It can be caused a number of factors, including:
- bacterial infection such as salmonella and E. coli
- parasites such as cryptosporidium and Giardia
- viral infection such as norovirus and viral hepatitis
- drugs such as misoprostol
- digestive disorders such as celiac disease and ulcerative colitis
- genetic disorders such as congenital chloride diarrhea
The primary symptom of osmotic diarrhea is loose and watery bowel movements. Other symptoms you might experience are:
Osmotic diarrhea can also have severe symptoms. See your doctor immediately if you have symptoms such as:
Osmotic diarrhea results when you eat foods that, instead of being absorbed, draw water into your intestine.
Ingredients that often cause osmotic diarrhea include:
- lactose, found in dairy products
- artificial sweeteners, such as aspartame and saccharine
- some carbohydrates found in fruit juices
Osmotic diarrhea can also be a side effect of medications and medical treatments including:
- certain antibiotics
- certain blood pressure medication
- laxatives that contain sodium phosphate, magnesium sulfate, and magnesium phosphate
- high-dose radiation therapy
- gallbladder removal
Osmotic diarrhea often lasts a few days. It generally responds to simple home treatments including diet adjustment and over-the-counter (OTC) medications such as loperamide (Imodium) and bismuth subsalicylate (Kaopectate, Pepto-Bismol).
There are changes you can make to your diet to potentially treat osmotic diarrhea. Doctors suggest limiting or avoiding the following foods:
- lactose-rich foods such as dairy products
- artificial sweeteners
- caffeinated products like coffee
- carbonated drinks
- legumes such as beans, lentils
- vegetables high in dietary fiber like broccoli and Brussels sprouts
- nuts and seeds
- whole wheat or corn products such as bran muffins and popcorn
They also encourage the consumption of:
- bread products made from refined white flour, such as plain white bread and pasta
- white rice
- cooked vegetables such as carrots and beets
- baked or broiled chicken without skin
- boiled potatoes without skin
In addition to checking with your doctor before taking any antidiarrheal medicine, you should also make an appointment if:
- your diarrhea lasts for more than two or three days
- you experience any severe symptoms such as high fever or bloody stool
Osmotic diarrhea is caused by eating certain kinds of food and usually lasts only a few days. It typically goes away once you stop consuming the offending food.
Many people address their diarrhea with OTC medicine and a diet change. If it lasts more than a few days or symptoms become more severe, a visit with your doctor is strongly suggested.