Symptoms of lactose intolerance in adults are bloating, abdominal pain, diarrhea, colic, and nausea. Symptoms can be resolved and relieved by making dietary adjustments such as avoiding milk and choosing medications such as lactase and lactobacillus. Lactose intolerance, also known as lactose intolerance, refers to the inability of a patient to digest lactose in dairy products due to reduced, deficient or even absent lactase activity, resulting in symptoms such as diarrhea, nausea, vomiting, hyperactive bowel sounds, constipation, etc. after consuming dairy products. The goal of treatment for lactose intolerance is to eliminate symptoms while avoiding nutritional deficiencies. For patients with primary lactase deficiency, reduction of lactose intake is advocated (not strictly prohibited); for patients with congenital lactase deficiency, lactose should be abstained for life; probiotic preparations such as Bacillus subtilis, Lactobacillus, Bacillus cereus and other medications such as lactase can be chosen for symptomatic relief. Lactose intolerance suggests prompt medical attention for targeted treatment. In addition, all of the above medications should be taken under the guidance of a doctor and should not be used without authorization.