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    Diarrhea: Why It Happens and How To Treat It

    When you have diarrhea, your bowel movements (stools) are loose and watery. It’s very common and although it feels bad, it's usually not serious.

    It typically lasts two to three days, and if you need to treat it, there are over-the-counter medicines, which means they don't need a prescription. 

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    For many people, diarrhea strikes once or twice each year. If you have certain conditions, such as irritable bowel syndrome, it can happen more often. 

    What Are the Symptoms?

    You may have:

    • An urgent feeling that you need to have a bowel movement
    • Thin or loose stools
    • Watery stool
    • Nausea and vomiting
    • Bloating in your belly
    • Cramps

    More serious symptoms include:

    • Blood, mucus, or undigested food in the stool
    • Weight loss
    • Fever

    If you have watery stools more than three times a day and you don't drink enough fluids, you could become dehydrated. That can be dangerous if it's not treated.

    What Causes Diarrhea?

    Usually, diarrhea is caused by a virus that infects the gut. Some people call it "intestinal flu" or "stomach flu." 

    It can also happen due to:

    • Alcohol abuse
    • Allergies to certain foods
    • Diabetes
    • Diseases of the intestines (such as Crohn's disease or ulcerative colitis)
    • Eating foods that upset the digestive system
    • Infection by bacteria (the cause of most types of food poisoning) or other organisms
    • Laxative abuse
    • Medications
    • Overactive thyroid (hyperthyroidism)
    • Radiation therapy
    • Running (Some people get “runner’s diarrhea”)
    • Some cancers
    • Surgery on your digestive system
    • Trouble absorbing some nutrients (Doctors call this “malabsorption.”)

    Diarrhea may also follow constipation, especially for people who have irritable bowel syndrome.

    When Should I Call My Doctor?

    Call your doctor immediately if you have:

    • Blood in your diarrhea or black, tarry stools
    • A fever that is high (above 101 F) or that lasts more than 24 hours
    • Diarrhea lasting longer than 2 days
    • Nausea or vomiting that prevents you from drinking liquids to replace lost fluids
    • Severe pain in your belly or rectum
    • Diarrhea when you come back from overseas travel

    Also, call your doctor right away if you have diarrhea and any of these signs of dehydration:

    • Dark urine
    • Smaller than usual amounts of urine or fewer wet diapers than usual in a baby or young child
    • Fast heart rate
    • Headaches
    • Dry skin
    • You feel irritable or confused


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