Diarrhea after eating pineapple nectar may be related to dietary impurity, cold and allergy. 1. Dietary impurity: If pineapple nectar is spoiled, or if you eat unclean pineapple nectar, it will lead to diarrhea due to inflammation of gastrointestinal tract after eating it. 2. Cold: consuming pineapple nectar directly from the refrigerator can cause severe irritation to the gastrointestinal tract, thus leading to diarrhea. 3. Allergy: diarrhea may be caused by an allergic reaction to pineapple nectar, usually accompanied by a rash, numbness of the lips and mouth, and in severe allergies, respiratory distress. Eating pineapple nectar diarrhea may be caused by other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.