GIT pathophysiology & Pharmacotherapy by UNZA School of Health Sciences - 3rd Year Pharmacology and Toxicology

Description

This document provides comprehensive notes on gastrointestinal pathophysiology and pharmacotherapy for third-year Pharmacology and Toxicology students within the Biomedical Sciences programme at the University of Zambia (UNZA) School of Health Sciences. The material begins with an overview of GIT structure and function, outlining common disorders such as peptic ulcer disease, gastroesophageal reflux disease (GERD), irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD). It details the pathophysiological imbalance between aggressive factors (acid, pepsin, H. pylori) and defensive factors (mucus, bicarbonate, prostaglandins) in peptic ulcers. The pharmacotherapy section systematically covers the classification, mechanism of action, adverse effects, and clinical use of key drug groups. These include H2-receptor antagonists (e.g., Ranitidine, Cimetidine), proton pump inhibitors (e.g., Omeprazole, Pantoprazole), prostaglandin analogs (Misoprostol), antacids, mucosal protective agents (Sucralfate, Bismuth subsalicylate), and prokinetic drugs (Metoclopramide, Domperidone). The notes also explain the ulcerogenic effects of NSAIDs and strategies for prophylaxis. Further sections address the pharmacotherapy of emesis (vomiting), detailing the roles of the chemoreceptor trigger zone and vomiting centre, and covering antiemetic drug classes like antihistamines, phenothiazines, 5-HT3 antagonists (e.g., Ondansetron), and dopamine antagonists. The management of diarrhoea includes discussions on oral rehydration therapy, antimotility agents (e.g., Loperamide), adsorbents, and drugs that modify fluid transport. The document concludes with treatments for constipation using various laxatives (stimulant, bulk, osmotic, stool softeners) and the management of IBS and IBD with antispasmodics, amitriptyline, 5-aminosalicylates, corticosteroids, and immunosuppressants. This resource is an essential study aid for university students, providing a detailed and structured review of GIT disorders and their corresponding drug therapies for examination preparation. Download these notes to strengthen your understanding of gastrointestinal pharmacology.