Eating pineapple mouth will bleed due to excessive consumption, body allergies and other aspects. 1. Excessive consumption: if the patient consumes a large amount of pineapple at one time, it will dissolve the triacylglycerol and blood clusters in the body, resulting in irritation of the lips and mouth, and the phenomenon of bleeding in the mouth. 2. Body allergy: pineapple contains pineapple protease, some patients are allergic to it, such substances to solve protein. If the patient’s mouth is already dry and cracked, eating pineapple will cause bleeding in the mouth. When patients eat pineapple mouth bleeding phenomenon, to immediately stop eating pineapple, with salt water or milk to the mouth for rinsing, can effectively alleviate the symptoms of bleeding, to promote the repair of the mucous membrane in the mouth, when the symptoms can not be relieved to seek medical attention immediately.