Cold and diarrhea can be caused by improper diet, gastrointestinal colds, or gastroenteritis in patients with colds. 1. Improper diet: the gastrointestinal function of patients with colds is weakened, such as patients with colds eat indigestible or irritating foods such as cold drinks, stimulating the gastrointestinal tract, which can lead to diarrhea. 2. Gastrointestinal colds: Gastrointestinal colds are mainly caused by respiratory syncytial virus, coxsackie virus and other infections, and can also be caused by influenza virus. The main symptoms of patients are nausea, vomiting, diarrhea, fever and so on. In addition, patients with gastrointestinal flu can also have headache, runny nose and other manifestations. 3. Gastroenteritis: Gastroenteritis is mainly caused by bacterial, viral and other pathogenic infections, and may also be caused by stress, drugs and other factors. Patients with gastroenteritis will experience nausea, vomiting, abdominal pain, diarrhea, fatigue and other symptoms. Diarrhea can also be caused by other diseases. If the symptoms do not improve or worsen, it is recommended that the patient should seek medical attention to clarify the cause of the disease and follow the doctor’s instructions.