Gastrointestinal Drugs: Peptic Ulcer Disease - Ch. 82

Question 1

Which cells secrete hydrochloric acid and pepsinogen?

Answer 1

HCl = Perietal cells
Pepsinogen = Chief cells

Question 2

What is the purpose of parietal cells?

Answer 2

Produce and secrete HCl to keep stomach at pH of 1 to 2

Question 3

What cells are the primary site of action for many acid-controller drugs?

Answer 3

Parietal cells

Question 4

What do ECL stomach cells secrete?

Answer 4

Secrete histamine which stimulate parietal cells

Question 5

What are stomach acid-related diseases?

Answer 5

Action of acidity on digestive tract integrity?

Question 6

What is the purpose of drug therapies for stomach acid related diseases?

Answer 6

Eradicate H. pylori if present in the stomach
Reduce gastric acidity
Enhance mucosal defenses

Question 7

90% of clients with what are found to have H. pylori?

Answer 7

Duodenal ulcers

Question 8

70% of clients with what are found to have H. pylori?

Answer 8

gastric ulcers

Question 9

What is used to eradicate H. pylori?

Answer 9

Antibacterials

Question 10

Rates of what is much less when H. pylori is eradicated?

Answer 10

Recurrence rates are much lower

Question 11

What are the inhibitors of Gastric acid secretion/action?

Answer 11

H2 antagonists
proton pump inhibitors
Antacids
other agents - protect mucosa

Question 12

What are kinds of antacids?

Answer 12

Magnesium salts
Calcium salts
Sodium bicarbonate
Aluminum salts

Question 13

What are H2 antagonists?

Answer 13

Reduce acid secretion
All available in OTC in lower dosage forms
Most popular drugs for treatment of acid-related disorders

Question 14

Examples of H2 antagonists?

Answer 14

Cimetidine (Tagamet)
Famotidine (Pepcid)
Ranitidine (Zantac)
Nizatidine (Axid)

Question 15

What is the mechanism of action of H2 antagonists?

Answer 15

Block histamine H2 receptors of acid-producing parietal cells
(receptor antagonist)
-Decreases HCl production

Question 16

What are H2 antagonists used for?

Answer 16

GERD (gastro-esophogeal reflux disease) -erosive esophagitis

PUD (peptic ulcer disease)
Adjunct therapy in control of upper GI bleeding
Pathological gastric hypersecretory
conditions

Question 17

What adverse effects are associated with h2 antagonists?

Answer 17

Low incidence of AEs
Cimetidine may induce impotence and gynecomastia (antiandrogenic effect)

In elderly; CNS depression, lethargy, confusion, renal/hepatic impairment

Question 18

What interactions does H2 antagonist: Cimetidine have?

Answer 18

Inhibits liver cytochrome P-450
Affects metabolism of ofter drugs causing increased drug levels e.g, warfarin

Question 19

extra care should be taken for patients with what who are taking Cimetidine?

Answer 19

Impaired renal or liver function

Question 20

Cimetidine should be used with caution in what group of patients?

Answer 20

Confused, disorientated or elderly patients

Question 21

Cimetidine should be taken 1 hour before what?

Answer 21

Antacids
-Affects absorption

Question 22

What are Proton pump inhibitors (PPI)?

Answer 22

Inhibits the pump that moves H+ into the stomach lumen
more effective than H2 antagonists

Question 23

What is the mechanism of action of PPIs?

Answer 23

Irreverisbly bind to H+/K+ ATPase enzyme (proton pump)

Question 24

What does normal acid secretion require?

Answer 24

Normal acid secretion needs parietal cell to synthesise new H+/K+ ATPase

Question 25

Examples of PPI?

Answer 25

Omeprazole lansoprazole rabeprazole pantoprazole (Pantoloc) -IV option esomeprazole (all very similar)

Question 26

Describe Omeprazole?

Answer 26

Enteric coated Broken down by acid

Question 27

What are proton pump inhibitors used for?

Answer 27

GERD maintenance therapy Erosive esophagitis Short-term treatment of active duodenal and benign gastric ulcers Zollinger-Ellison syndrome (gastrin-producing tumour)

Question 28

What are PPI safe for?

Answer 28

Short-term therapy - 4-8 weeks

Question 29

What adverse effects are associated with PPI?

Answer 29

Incidence of AE low and uncommon -Headaches, Nausea, vomiting, diarrhea

Question 30

When should you use PPI with caution?

Answer 30

Liver disease pt

Question 31

What drug interactions do PPI have?

Answer 31

May inhibit the absorption of drugs that require an acidic GI environment for absorption e.g, Ketoconazole (anti fungal)

Question 32

What is the typical therapy for H. pylori infection?

Answer 32

"triple therapy" -Antibiotics e.g, amoxicillin + clarithromycin -Proton pump inhibitor e.g, omeprazole 7-14 days

Question 33

proton pump inhibitors may cause increase serum levels of what?

Answer 33

Diazepam phenytoin increased chance for bleeding with warfarin (P450 inhibition)

Question 34

What should you teach a client if they are taking omeprazole?

Answer 34

Swallow it whole -Not crushed, opened or chewed because of the enteric coating It may be given with antacids Short term treatment only

Question 35

What is the mechanism of action of Antacids?

Answer 35

Chemically neutralise acid -Do not prevent acid production

Question 36

What OTC formulations of Antacids are available?

Answer 36

Capsules, tablets Powders Chewable tablets Suspensions Effervescent granules and tablets

Question 37

What are the salts in aluminium salts?

Answer 37

Carbonate, hydroxide salts

Question 38

What can aluminium salts may cause?

Answer 38

constipation Often with magnesium salts to counteract constipation (can cause diarrhea)

Question 39

Examples of aluminium salts?

Answer 39

aluminum hydroxide (amphogel) Aluminum carbonate Combination products (aluminium and magnesium)

Question 40

What are the salts in magnesium salts?

Answer 40

Carbonate, hydroxide and oxide trisilicate

Question 41

What do magnesium salts commonly cause?

Answer 41

Diarrhea (usually used with other agents to contract diarrhea)

Question 42

When is magnesium slat use dangerous?

Answer 42

If you have renal failure -accumulation

Question 43

Examples of magnesium salts?

Answer 43

Hydroxide salt; Magnesium hydroxide Carbonate salt combination products (Al + Mg)

Question 44

What salts are Calcium salts?

Answer 44

many but carbonate is most common

Question 45

What may be caused by calcium salts?

Answer 45

Constipation Kidney stones

Question 46

How is calcium salts often advertised?

Answer 46

Extra source of dietary calcium

Question 47

Example of calcium salts?

Answer 47

Calcium carbonate (TUMS)

Question 48

Describe sodium bicarbonate?

Answer 48

Highly soluble Quick onset, short duration

Question 49

What may be caused by sodium bicarbonate?

Answer 49

May cause metabolic alkalosis

Question 50

The sodium content in sodium bicarbonate may cause problems in clients with what conditions ?

Answer 50

heart failure hypertension renal insufficiency

Question 51

What adverse effects are associated with antacids?

Answer 51

Minimal and depend on compound used Aluminum and calcium salts = constipation Magnesium salts = diarrhea Calcium carbonate = constipation, gas and belching

Question 52

What drug interactions do antacids have?

Answer 52

May reduce absorption of other drugs if given at the same time Can cause chelation

Question 53

What is chelation?

Answer 53

Chemical binding, or inactivation, of another drug - Produces insoluble complexes - reduced drug absorption eg tetracycline

Question 54

What should be assessed for before antacid administration?

Answer 54

Allergies preexisting conditions such as: Fluid imbalances Renal disease HF Pregnancy GI obstruction

Question 55

Clients with heart failure and hypertension should use which antacids?

Answer 55

Low sodium antacids

Question 56

Most medications should be given how many hours after an antacid?

Answer 56

1-2 hours after giving an antacid

Question 57

Antacids may cause ____________ _______________ of enteric coating meds

Answer 57

Premature dissolving

Question 58

Antacids should be administered with what to enhance dispersion?

Answer 58

At least 240 mL of water -Not needed for rapid dissolving forms

Question 59

What may aggregate underlying GI conditions when using antacids?

Answer 59

Caffeine alcohol harsh spices black pepper

Question 60

What are the other agents that protect the mucosa?

Answer 60

Sucralfate Misoprostol (Cytotec)

Question 61

What is sucralfate?

Answer 61

Cytoprotective agent Forms gel with mucus in low pH Attracted to and binds to the base of ulcers and erosions (forms a protective barrier) Inhibits pepsin

Question 62

What is sucralfate used for?

Answer 62

Intestinal erosions

Question 63

What may be caused by sucralfate?

Answer 63

Constipation Nausea Dry mouth

Question 64

There is little absorption of sucralfate in what area?

Answer 64

gut

Question 65

Sucralfate may impair the absorption of what the drugs?

Answer 65

Tetracycline Digoxin

Question 66

Why might sucralfate be used in chronic renal failure?

Answer 66

Reduce phosphate levels because it binds with phosphate

Question 67

What is Misoprostol?

Answer 67

Synthetic prostaglandin (PGE1) analogue -Does the job of endogenous PGs (PHI2 and PGE2) Prostaglandins have cytoprotective activity

Question 68

What does cytoprotective activity do?

Answer 68

Production of mucous and bicarbonate Reduce acid secretion Promote local cell regeneration help maintain mucosal blood flow

Question 69

What is misoprostol used for?

Answer 69

Reduce gastric effects of NSAIDs

Question 70

When is misoprostol not used?

Answer 70

Pregnancy -Terminates pregnancy

Question 71

Example of misoprostol combination tablets?

Answer 71

Arthrotec = Diclofenac + misoprostol

Question 72

What adverse effects are associated with misoprostol?

Answer 72

Therapeutic doses for duodenal ulcers often produce: abdominal cramps diarrhea PGE may cause contraction of smooth muscle-containing tissues