Metoclopramide is mainly used clinically for nausea and vomiting caused by various reasons, and it is used before duodenal intubation and barium meal examination to reduce nausea and vomiting reactions, which is conducive to the smooth conduct of the examination. Contraindications: allergic to drug components, patients with epilepsy, gastrointestinal bleeding, patients with mechanical intestinal infarction, patients with pheochromocytoma, pregnant and lactating women are prohibited. Patients with hepatic and renal insufficiency should appropriately reduce the dose of the drug. Metoclopramide is a dopamine second receptor antagonist, which can act on the medullary vomiting center, raise the vomiting threshold, and exert a powerful central antiemetic effect. The main adverse effects are lethargy, irritability, and fatigue. Occasionally, breast swelling and pain, nausea, constipation, diarrhea, sleep disturbance and dizziness may occur. Seek medical attention for any discomfort and use the drug as prescribed.