Patients with lactose intolerance primarily show clinical symptoms related to the digestive tract such as bloating, increased bowel sounds, intestinal colic, diarrhea, nausea, vomiting, and more. Some patients experience reduced intestinal motility, leading to constipation, and the severity of symptoms is somewhat related to the amount of dairy products consumed. If a patient with lactose intolerance is experiencing nausea, they should eat light foods and avoid dairy products as much as possible. Patients with lactose intolerance should seek medical attention in a timely manner. When visiting a doctor, they should provide detailed medical history information to help the doctor determine the correlation between the clinical symptoms and lactose intolerance.