peptic ulcer disease (acid)

Question 1

stomach secretions

Answer 1

• hydrochloric acid (parietal cells)
• pepsinogen (chief cells)
• mucus
• bicarbonate
• prostaglandins

Question 2

parietal cells

Answer 2

produce and secrete HCl to keep stomach pH at 1-2
- primary site of action for many acid-controller drugs

Question 3

ECL cells

Answer 3

secrete histamine
- stimulate parietal cells

Question 4

stomach acid related diseases

Answer 4

action of acidity of digestive tract integrity
lay terms for stomach problems (indigestion, sour stomach, heartburn, acid stomach)
- PUD: peptic ulcer disease
- GERD: gastroesophageal reflux disease

Question 5

aggressive factors against stomach (makes ulcers)

Answer 5

• h. pylori
• NSAIDs
• acid
• pepsin
• smoking

Question 6

defensive factors for stomach (protect from ulcers)

Answer 6

• mucus
• bicarbonate (neutralize)
• blood flow
• prostaglandins

Question 7

what do PUD drug therapies do?

Answer 7

• eradicate h.pylori if present in stomach
• reduce gastric acidity
• enhance mucosal defences

treat ulcer but also prevent it from happening in the future

Question 8

h pylori

Answer 8

helicobacter pylori
- 90% duodenal ulcers, 70% gastric ulcers
- antibacterials eradicate it
- recurrence rates much less with eradication
- releases its own chemicals to protect from acid

Question 9

inhibitors of gastric acid secretion/action

Answer 9

• H2 antagonists
• Proton pump inhibitors
• antacids (Mg, Ca, Al salts)
• other agents: protect. mucosa

Question 10

H2 antagonists

Answer 10

histamine 2 receptors: inhibit production of acid
- reduce acid secretion
- OTC in low dose
- most popular

Question 11

H2 antagonist examples

Answer 11

• cimetidine (adverse effects)
• famotidine
• ranitidine
• nizatidine

Question 12

H2 antagonist mechanism of action

Answer 12

block h2 receptors of acid-producing parietal cells
- decreased HCl production
- allows ulcer to heal due to less acidity

Question 13

H2 antagonist indications

Answer 13

• GERD - erosive esophagitis
• PUD
• adjunct therapy in control of upper GI bleeding
• pathological gastric hypersecretory conditions

Question 14

H2 antagonists adverse effects

Answer 14

low incidence of AE
- cimetidine may induce impotence and gynecomastia (antiandrogenic effect - sex hormones)
- in elderly may see CNS depression (lethargy), confusion because of renal/hepatic impairment

Question 15

H2 antagonists drug interactions

Answer 15

Cimetidine
- inhibits liver cytochrome p-450
- affect metabolism of other drugs causing increased drug levels (warfarin - increased bleeding)

Question 16

H2 antagonist client implications

Answer 16

cimetidine:
- care in pt with impaired renal/liver function (metabolism and excretion)
- caution with pt who are confused, disoriented, elderly
- do not take with antacids, affects absorption (take at least an hour apart)

Question 17

proton pump inhibitors (PPI)

Answer 17

inhibit production of acid
- inhibition of the pump that moves H+ ions into stomach lumen (acidity)
- more effective than H2 antagonists

Question 18

PPI mechanism of action

Answer 18

• irreversibly bind to H+/K+ ATPase enzyme pump
• normal acid secretion now requires parietal cell to make new atpase

Question 19

PPI examples

Answer 19

• omeprazole
• lansoprazole
• rabeprazole
• pantoprazole
• esomeprazole

Question 20

omeprazole

Answer 20

enteric coated (avoid being broken down by acid in stomach to it can be absorbed in small intestine)
- broken down by acid
- absorbed in small intestine into circulation then brought to stomach

Question 21

PPI indications

Answer 21

• GERD maintenance therapy
• erosive esophagitis
• short term treatment of active and benign gastric ulcers
• gastric-producing tumour (zollinger-ellison syndrome)

Question 22

PPI adverse effects

Answer 22

safe for short term therapy (4-8 weeks)
- incidence low and uncommon
- headaches, GI (n&v, diarrhea)
- caution in pt with liver disease

Question 23

PPI drug interactions

Answer 23

may inhibit absorption of drugs that require an acidic GI environment for absorption
- pH levels raised to drugs that need a low pH to be absorbed can’t be, pass through stomach
- ketoconazole (antifungal)

Question 24

treatment for h pylori infection

Answer 24

triple therapy
- 2 antibacterials: amoxicillin + clarithromycin
- PPI: omeprazole
- 7-14 days
- 2 antibacterials reduce resistance development

Question 25

client care: PPI

Answer 25

omeprazole: - capsule swallowed whole (enteric coated - not crushed, opened or chewed) - may be given with antacids - short term treatment

Question 26

antacids mechanism of action

Answer 26

chemically neutralize acid - do not prevent acid production - no absorbed into circulation, works in the lumen - add on for PUD, not as good on its own

Question 27

antacids examples

Answer 27

alone or in combination: - aluminum salts - magnesium salts - calcium salts - sodium bicarbonate

Question 28

aluminum salts

Answer 28

- may cause constipation - often used with magnesium salts to counteract constipation (cause diarrhea) aluminum hydroxide aluminum carbonate

Question 29

magnesium salts

Answer 29

- commonly cause diarrhea - used with other agents to counteract - dangerous when used with renal failure (accumulation and kidneys not getting rid of it) - magnesium carbonate, hydroxide, oxide, trisilicate

Question 30

calcium salts

Answer 30

- may cause constipation - possible kidney stones - calcium carbonate - often advertised as dietary carbonate

Question 31

sodium bicarbonate

Answer 31

rare use - highly soluble - quick onset, short duration - may cause metabolic alkalosis - sodium content may cause problems in clients with HF, hypertension, or renal insufficiency

Question 32

antacids adverse effects

Answer 32

minimal and depend of the compound used - aluminum and calcium: constipation - magnesium: diarrhea - calcium carbonate: constipation, gas, belching (often combined with simethicone)

Question 33

antacids drug interactions

Answer 33

absorption of other drugs: - may reduce absorption of other drugs given at same time (H2) chelation (binding together) - chemical binding or inactivation of another drug - produces insoluble complezes - reduce absorption - eg tetracycline

Question 34

care implications antacids

Answer 34

assess for allergies and preexisting conditions that may restrict the use of antacids - fluid imbalances, renal disease, HF, pregnancy, GI obstruction client with HR or hypertension should use low-sodium antacids

Question 35

client implications antacids cont

Answer 35

- root cause of many drug interactions - give meds 1-2 hours after antacid - antacids may cause premature dissolving of EC meds - administer with 240 ml h20 to enhance dispersion - caffeine, alcohol, harsh spices, and black pepper may aggravate underlying GI condition

Question 36

other agents: protect mucosa

Answer 36

- sucralfate: bind directly to ulcer surface - misoprostol: prostaglandin agent

Question 37

sucralfate

Answer 37

- cytoprotective agent - used for intestinal erosions - forms gel with mucus in low pH - attracted to and binds to base of ulcers and erosions forming a protective barrier - protects cells and allows recovery - inhibits pepsin - do not administer with antacids

Question 38

sucralfate cont

Answer 38

- little absorption from the gut - may cause constipation, nausea, and dry mouth - may impair absorption of other drugs (tetracycline, digoxin), sticks to drugs and makes them less effective - binds with phosphate (may be used in chronic renal failure to reduce phosphate levels)

Question 39

misoprostol

Answer 39

synthetic prostaglandin - does job of PGI2 and PGE2 prostaglandins have cytoprotective activity - produce mucus and bicarbonate (neutralize) - reduce acid secretion - promote local cell regeneration - help to maintain mucosal blood flow

Question 40

misoprostol cont.

Answer 40

reduce gastric effects of NSAIDs (ASA, diclofenac) - combination tablets (arthrotec = diclofenac + misoprostol) not in pregnancy - used to terminate pregnancy (smooth muscle constriction - medical abortion)

Question 41

misoprostol adverse effects

Answer 41

abdominal cramps, diarrhea - contraction of smooth muscle