This chapter describes the gastrointestinal drugs, which include aluminum hydroxide, domperidone, itopride, esomeprazole, lansoprazole, metoclopramide, mosapride, omeprazole, ondansetron, promethazine, pantoprazole, rabeprazole, ranitidine, levosulpiride, dexrabeprazole, ramosetron, magnesium hydroxide, simethicone, famotidine, ilaprazole, oxethazaine, bacillus clausii, lactitol, ispaghula husk, L-ornithine L-aspartate, and glycopyrronium bromide. Nausea and vomiting associated with GI disorders, functional dyspepsia, and motility disorders such as hypomotility, and irritable bowel syndrome (IBD) are the indications of domperidone. Erosive esophagitis, nonsteroidal anti-inflammatory drugs (NSAIDs), Zollinger-Ellison syndrome, and GERD are the indications of esomeprazole. Peptic ulcer, hypersecretory conditions, acid-related dyspepsia, prevention and treatment of NSAID-related ulcers, and erosive esophagitis are the indications of lansoprazole.