Caffeine and Loose Stools

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Caffeine in excessive doses can cause loose stools and diarrhea. If you notice that whenever you consume caffeine you develop diarrhea, you need to call your doctor. It is possible that you are sensitive to caffeine or that other factors may be contributing to your symptoms. For example, caffeine is in chocolate, which may trigger diarrhea if you’re lactose intolerant or allergic to one or more of the ingredients in the chocolate product. Diarrhea that lasts for more than three days may be a sign of a more serious condition.


Caffeine is a stimulant drug that naturally occurs in various foods and beverages. Common foods and beverages with caffeine include chocolate, coffee, tea, kola nuts and sodas. Caffeine is also available in supplement form for mental alertness and helping you stay awake. Some pain relieving medications contain caffeine to make the pain relieving drug more effective. Caffeine affects your central nervous system and can cause various side effects, such as sleepiness, irritability and nervousness. Stop using caffeine if you develop any adverse reactions.

Loose Stools

Loose stools may be a sign of diarrhea. If you experience frequent bowel movements that are watery and loose, you most likely have diarrhea. Diarrhea is a concerning symptom because it can quickly lead to dehydration. Loose stools are a common side effect of ingesting too much caffeine. If you notice that your lips, mouth or skin are dry, you feel tired and extremely thirsty, call your doctor because you may be dehydrated.

Elimination Diet

Reduce the amount of caffeine you ingest daily to see if it helps your diarrhea subside. Once your bowel movements return to normal, add a small amount of caffeine to see how your body reacts. Keep a record of how much caffeine you drink daily and how it affects your bowel movements.

Allergy and Intolerance

The loose stools may not be directly related to the ingestion of caffeine, but may be the result of one or more of the ingredients in the product that contains caffeine. For example, most people add cream to their coffee or eat chocolate products that contain milk, nuts and soy proteins. If you’re allergic to any ingredients in the food or beverage that contains caffeine, you will develop diarrhea and other systematic symptoms within minutes of ingesting the product, according to the University of Maryland Medical Center. Lactose intolerance is a common digestive disorder, where your digestive system cannot digest the sugar in milk, which will cause diarrhea.