Gastrointestinal Drugs

1. Gastrointestinal Drugs Pharmacology : NURS 1950

2. Objective 1: list the components of gastric juice that contribute to the pain associated with peptic ulcers • HCL, Pepsin, gastrin, lipase and histamine

3. Obj. 2 describe path of gastric secrections • Chief cells • Secrete pepsinogen • Parietal cells • Stimulated by acetylcholine to produce HCL and gastrin • Intrinsic factor • Mucous cells • Coats stomach wall

4. Objective 3: list drugs considered to be ulcerogenic • Smoking • NSAIDS • Corticosteroids • ASA

5. Objective 4: explain the actions of the antiulcer drugs • Decrease acidity • Block histamine receptors • Gastrointestinal prostaglandins

6. Gastric acid pump inhibitors • Coating agents • Prokineticagents • Antispasmodic agents

7. Objective 5: describe the pain reducing effects of antacid • Raise the pH of gastric contents • Higher pH, less acidity • Decreased pain

8. Objective 6: identify the features of an ideal antacid • Cheap • Effective • No constipation or diarrhea • No systemic effects • No rebound acidity

9. Objective 7: differentiate between the various antacids

10. Riopan, Maalox, Mylanta II, • low sodium • Calcium carbonate, Aluminum hydroxide: constipation • Magnesium: • diarrhea, electrolyte imbalance • Calcium carbonate & sodium bicarbonate: rebound acidity • Simethicone: • defoamingagent Alginic acid: highly viscous solution— sodium alginate

11. Objective 8: describe the nursing implications associated with antacid therapy • What are the assessments and interventions the nurse would do for a client taking an antacid? • Renal • GI • Schedule of meds

12. Objective 9: state the mechanism of action of anticholinergic and antispasmodic agents

13. Anticholinergics and antispasmodics the same • Drugs include belladonna, probanthine, bentyl • Used for spastic conditions of GI tract, peptic ulcers and irritable bowel syndrome • Block parasympathetic nervous system • Activity is systemic • What would you see with anticholinergics?

14. Which clients should not use anticholinergics?

15. Objective 10: identify appropriate nursing actions relative to caring for clients receiving antispasmodic drugs • Assess: mental status, teach about orthostatic hypotension • In the elderly: increased constipation • If arrhythmia or palpitations: stop the drug, call the physician

17. Objective 11: describe the effects and uses of H2 receptor antagonists, and proton pump inhibitors • H2 receptor antagonists • Block histamine 2 receptors • Raises pH of gastric contents • Used for GERD, duodenal ulcers, Zollinger-Ellison syndrome • Used to prevent or treat stress ulcers

18. Drugs include • Cimetidine (Tagamet) • Famotidine (Pepcid) • Nizatidine (Axid) • Rantidine (Zantac) • Prototype

19. Drugs can cause • Dizziness, HA, diarrhea, constipation • If confusion, disorientation, hallucination, see MD • Can cause gynecomastia, hepatotoxicity

20. Proton pump inhibitors • Inhibit gastric acid pump • Treat: severe esophagitis, GERD, gastric and duodenal ulcers, Zollinger-Ellison syndrome • Can be used with antibiotics for H pylori • S/E: diarrhea, HA, muscle pain and fatigue • If rash: call MD

21. Drugs include • Esomeprazole (Nexium) • Lansoprazole (Prevacid) • Omeprazole (Prilosec) • prototype • Pantoprazole (Protonix) • Rabeprazole (Aciphex)

22. Objective 12: Explain the nursing interventions associated with H2 receptor antagonists and proton pump inhibitors • Consult with MD • Avoid ETOH • Correct timing • No smoking • Immediately report blood

23. Objective 13: identify causes of constipation • Objective 14: explain the uses of laxatives and cathartics • Objective 16: describe the actions of the types of laxatives • Objective 17: identify laxatives according to type

24. Causes of constipation • What are some things or conditions that can cause constipation?

25. laxatives • Act three ways • Affect fecal consistency • Increase fecal movement • Remove stool from rectum

26. Laxatives OTC; misused • Dependence • Damage bowel • Cause problems in bowel

27. Contraindications, Precautions • Caution: surgical abdomen; appendicitis; N/V; fecal impaction; intestinal obstruction; undiagnosed abdominal pain • Contraindicated: hypersensitivity

28. Groups of Laxatives • Bulk-forming • Emollient • Hyperosmotic • Saline • Stimulant

29. Mechanism of action • Bulk-forming: natural fiber-like • Absorb water • Distends bowel • Initiates reflex bowel activity • Best for long term use

30. Emollient laxatives • Stool softener (Docusate salts) • Lowers surface tension • Allows more fat & water to be absorbed • When should these be used?

31. Lubricant laxative (mineral oil) • Lubricates fecal material & intestinal wall • Prevents H20 from leaking out of gut • Stool expands & softens

32. The emollients and lubricants do not seem to increase peristalsis • Oils a problem in constantly recumbent clients

33. Hyperosmotic increase water content in large intestine • Distends bowel • Increases peristalsis • Evacuates the bowel • Non-absorbable ion exchange • Used before diagnostic tests

34. Saline laxatives increase osmotic pressure in small intestine • Inhibit absorption of water & elytes • Increase amount of water & elytes

35. Results: watery stool • Increased distention of bowel • Promotes peristalsis & evacuation • Example: citrate of magnesia

36. Stimulant laxatives stimulate nerves • Increases peristalsis • Increase fluid in colon • Increases bulk • Softens stool

37. Drug effects • Few systemic effects • Primary site of action the gut • Therapeutic Uses • Common constipation • Bowel preparation pre-op, diagnostic tests

38. Side Effects/Adverse Effects • Bulk forming: impaction above strictures, fluid overload, electrolyte imbalance, gas • Emollient: skin rash, decreased absorption vitamins, lipid pneumonia, elyte imbalance • Hyperosmotic: abdominal bloating, rectal irritation, elyte imbalance

39. Saline: magnesium toxicity, elyte imbalance, diarrhea, increased thirst • Stimulant: nutrient malabsorption, gastric irritation, elyte imbalance, discolored urine, rectal irritation

40. Interactions • Bulk-forming: interfere with absorption antibiotics, digoxin, salicylates, oral anticoagulants • Mineral oil: decrease absorption fat soluble vitamins • Hyperosmotic: increased CNS depression with barbiturates, general anesthetics, opioids, antipsychotics

41. Oral antibiotics decrease effect of lactulose • Stimulants: decrease absorption antibiotics, digoxin, tetracycline, oral anticoagulants

42. Objective 15: identify features of an ideal laxative and cathartic • What do you think makes an ideal laxative?

43. Obj 18- describe nursing interv associated with admin of laxatives. • Assess: drugs client takes including OTC and herbs • Assess bowel elimination pattern • Assess diet and fluid intake • Assess activity and exercise • Assess for travel, dehydration • Assess for any past GI problems

44. Objective 19: identify causes of diarrhea • What things, conditions can cause diarrhea?

45. Objective 20: describe the uses of antidiarrheal agents • Objective 21: identify the antidiarrheal agents

46. Antidiarrheal drugs: local or systemic action • Local: adsorb water to cause a formed stool • Systemic: act on autonomic nervous system to decrease peristalsis

47. Antidiarrheals • Groups based on mechanism of action • Adsorbents • Antimotility • Bacterial replacement • Antisecretory • Enzymes

48. Mechanism of action • Treat underlying cause • Adsorbents: coat walls of GI tract; bind causative bacteria, toxin • Bismuth subsalicylate (Pepto-Bismol) • Attapulgite (Kaopectate) • Aluminum hydroxide (AlternaGel, Maalox) • Kaolin-pectin

49. Anticholenergics • Decrease: peristalsis, muscle tone • Use with adsorbents, opiates • Examples: • Atropine • Hyoscyamine • Hyosine

50. Opiates • Decrease bowel motility • Reduce pain • Increased absorption of water & elytes (absorption time)