Saline can be used for enemas. However, it should only be used under certain necessary circumstances, and for childhood, the casual use of saline enemas is not recommended if it is only for the treatment of constipation. Saline itself is a liquid with osmotic pressure equal to that of the body’s crystals, and is relatively safe to use. However, if the enema is used frequently, it may lead to diarrhea and other conditions, and excessive dehydration may cause electrolyte disorders and anal injury. Saline enemas can be used to treat constipation and promote the elimination of persistent feces. Saline enemas can also be effective in promoting the elimination of poisons if harmful substances are accidentally ingested. In addition, it can also be used in fever-reducing treatment, which should usually be operated in the hospital according to the doctor’s instructions, and should not be operated by oneself. If the operation technique is not appropriate, it may cause localized damage to the anus.