Gastrointestinal drugs

TABLE 1.11 Some of the Most Commonly Prescribed Gastrointestinal Drugs in the Untied States 

Prevacid (lanoprazole) 25.6(1.2) 23.6 (0.8) 22.2 (1.0) Block the enzyme that pumps H into the secretory side of the parietal cells of the stomach. 

Disturbances in the GI system, such as nausea and cramps, may occur with laxative use. With prolonged use, serious lower GI irritation, including spastic colitis, may occur. Fluid and electrolyte abnormalities are also a potential problem. Excessive loss of water and the concomitant loss of electrolytes may transpire, resulting in dehydration and possible acid-base imbalances.44 These abnormalities are especially significant in older or debilitated patients. Finally, chronic administration may result in a laxative dependence when bowel evacuation has become so subservient to laxative use that the normal mechanisms governing evacuation and defecation are impaired. 

Several other types of drugs are administered for specific purposes in controlling GI function. These other drugs are introduced here only to alert the reader to their existence. For a more detailed description of the use of any of these agents, one of the drug indexes such as the Physician s Desk Reference (PDR) should be consulted. 

These agents are administered to aid in the digestion of food. The primary digestant preparations contain pancreatic enzymes or bile salts. Pancreatic enzymes such as amylase, trypsin, and lipase are responsible for digestion of carbohydrates, proteins, and lipids, respectively. These enzymes are normally synthesized in the pancreas and secreted into the duodenum via the pancreatic duct. Bile salts are synthesized in the liver, stored in the gallbladder, and released into the duodenum via the common bile duct. Bile salts serve to emulsify lipids in the intestinal tract and are important in lipid digestion and absorption. 

Digestant preparations are used to replace digestive constituents in the stomach and upper small intestine whenever the endogenous production of these 

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Discuss the uses, general drug adions, general adverse readions, contraindications, precautions, and interadions associated with gastrointestinal drugs. 

Discuss important preadministration and ongoing assessment adivities the nurse should perform on the patient taking a gastrointestinal drug. 

Discuss ways to promote an optimal response to therapy, how to manage common adverse reactions, and important points to keep in mind when educating patients about the use of gastrointestinal drugs. 

Fiebrig I (1995) Solution Studies on the Mucoadhesive Potential of Various Polymers for use in Gastrointestinal Drug Delivery Systems. PhD Thesis, University of Nottingham, Nottingham, UK... 

Ho NFH, JY Park, PF Ni, WI Higuchi. (1983). Advancing quantitative and mechanistic approaches in interfacing gastrointestinal drug absorption studies in animals and man. In WG Crouthamel, A Sarapu, eds. Animal Models for Oral Drug Delivery in Man In Situ and In Vivo Approaches. Washington, DC APh/APS, pp 27-106. 

The field of gastrointestinal drugs saw the entry of Amitiza (lubiprostone), the first selective and locally acting CIC-2 chloride channel activator, for the... 

The systemic availability of an inhaled glucocorticoid represents the additive and complex combination of pulmonary and gastrointestinal drug absorption. Absorption is influenced by many factors, including delivery device, the use of a spacer, the particle size of the inhaled drug, and the absorption and metabolism of the swallowed drug (1). 

Welling PG In uence of food and diet on gastrointestinal drug absorption a rd F fcwrmacokinet Biopharpi 1977 5 291-334. 

Basit, A.W., et al. 2004. The use of formulation technology to assess regional gastrointestinal drug absorption in humans. Eur J Pharm Sci 21 179. 

A. H. Staib, B. G. Woodcock, D. Loew, and O. Schuster, Chapter 8 Remote control of gastrointestinal drug delivery in man (L. F. Prescott, and W. S. Nimmo, eds.), Novel Drug Delivery and 1st Therapeutic Application, J. Wiley Sons, Chichester, UK, 1989, pp. 79-88. 

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