Before the operation is generally not recommended to take cold medicine, because the ingredients inside the cold medicine may interact with the anesthetic, which will affect the effect of the anesthetic itself. If there is paracetamol in it, it may have a mutual reaction with the anesthetic, which will deepen the drug effect of the anesthetic, thus leading to a higher depth of anesthesia, which can make the patients who are under general anesthesia after the surgery, may stipulate that the awakening time will be relatively prolonged. In addition, generally eight hours before the operation should be fasting, if within half an hour accidentally ate cold medicine, and drink water can not do the operation, because there may be vomiting in the process of surgery, if the vomitus mistakenly inhaled into the trachea or lungs, may lead to asphyxia or later inhalation of pneumonia.