The main differences between compound allantoin and omeprazole are different components, different mechanisms of action and adverse reactions, and should be used under the guidance of a doctor. 1. Different components, compound allantoin is composed of allantoin and aluminum hydroxide, for the antacid and gastric mucosal protection drugs, omeprazole is mainly composed of omeprazole sodium, magnesium, is a proton pump inhibitor. 2. Different effects, compound allantoin mainly through the neutralization of gastric acid, in order to relieve acid reflux caused by excessive gastric acid, abdominal pain, heartburn, etc., omeprazole is through the inhibition of gastric mucosa wall cell hydrogen, potassium, ATPase, that is, inhibition of the proton pump, so as to achieve the purpose of inhibition of gastric acid secretion, used for gastric and duodenal ulcers, reflux esophagitis, stress ulcers, gastrinomas and so on. 3. Adverse reactions are different, compound allantoin will appear dry mouth, stomach discomfort, individual breast swelling and pain, long-term use of elderly patients will appear osteoporosis, adverse reactions are not clear. Adverse reactions of omeprazole are commonly diarrhea, vomiting, nausea, constipation, etc., and occasionally fatigue, dizziness, etc.. Severe renal insufficiency, pregnant women, lactating women and infants, allergy is prohibited. Both compound allantoin and omeprazole are prescription drugs and should be used under medical supervision to avoid adverse reactions.