Diarrhea and anal fire are often caused by the following reasons: 1. Hemorrhoids: After diarrhea it can easily lead to the onset of hemorrhoids, the anal part will be painful, and sometimes there is a swelling prolapse, you need to go to the hospital general surgery or anorectal surgery as soon as possible to clarify. If it is the disease, you need to actively adjust your diet, for example, try not to drink drinks containing alcohol, do not eat too spicy food, and do not eat pickled food, etc., can be appropriate intake of fresh fruits and green vegetables. The actual fact is that you will be able to get a lot more than just a few of these. If the disease, you can first conservative treatment, if necessary, surgery. 3, the anal part of the break: can also cause dilution after the anal hot and spicy feeling.