Pineapple eat mouth rotten to stop eating pineapple, pay attention to oral hygiene, drink more water, you can supplement vitamins, local can be light saline wet compresses, apply gentamycin ointment and so on. Pineapple contains an enzyme called pineapple prion enzyme, which can stimulate the oral mucosa and cause xerostomia, so part of the population will have ulcers on the corners of the mouth after eating pineapple. The above situation need to stop eating pineapple, avoid re-exposure to pineapple prion enzyme; pay attention to oral hygiene, avoid licking lips and mouth with the tongue, drink more water, to promote the metabolism of the enzyme in the body; can be supplemented with vitamins, such as vitamin B2, etc.; the local can be used to apply a compress of light saline, and apply gentamycin ointment and so on. Pineapple eat mouth rotten suggest timely dermatology consultation, under the guidance of the doctor correct treatment, to avoid delaying the condition.