Dacronin Hydrochloride Gum Paste is a local anesthetic. It is used for anesthesia and lubrication of the larynx before endoscopy of the upper gastrointestinal tract, and also for eliminating foam in the lumen for a clear view. Shake the solution appropriately before taking it, and before gastroscopy, hold 8 to 10 ml of the solution in the throat and swallow it slowly for about 10 to 15 minutes before examining the gastroscope. Ask to resume eating half an hour after the gastroscopy and try to eat a semi-liquid diet or soft food. Avoid the effects of local anesthetic drugs.