The time for patients to take cold medicine is preferably about half an hour after meals. Because it is easy to irritate the mucous membrane of the gastrointestinal tract when it is taken before meals. As most of the current cold and flu medicines are compound preparations, which contain ingredients such as antiviral drugs and antipyretic and analgesic drugs, it is easy to cause irritation to the mucous membrane of the gastrointestinal tract, which can cause gastric acid, bloating, nausea, vomiting and other symptoms. Therefore, patients take the drug after meals, which can reduce gastrointestinal reactions and will not affect the absorption and utilization of drugs. In addition, patients need to pay attention to more cold medicines contain antihistamines, such as Benadryl, chlorpheniramine, etc., these drugs can quickly and effectively relieve the symptoms caused by colds. But at the same time will have a significant inhibition of the nerve center, thus producing sedation local anesthesia effect. Therefore, after taking the drug, there will be people faint, dizziness, drowsiness and other phenomena, it is not recommended to do high-altitude work and fine work, and also not recommended to drive, driving a boat, piloting an airplane and so on, in order to avoid the danger. If the nature of work requires that the above operations must be done, it is recommended to take cold medicines that do not contain antihistamine ingredients. Patients should eat light, soft, easy-to-digest food during cold and flu, and avoid overeating. And do not stack medicines when you have a cold, so as to avoid allergic reactions, affecting the health of the organism.