Gi Drugs

Front 1

Antacids
1. MOA
2. systemic vs. nonsystemic
3. uses
4. Drug Interactions

Back 1

1. basic compound that reacts with gastric acid to form salt and water (inc gastric pH), also dec pepsinongen > pepsin
2. systemic (NaHCO3) can cause metabolic alkalosis vs. nonsystemic (Al(OH3), Mg(OH)2, CaCO3) that aren't absorbed from stomach
3. GERD, ulcer disease, stress ulcer prophylaxis, Mg/Ca supp, tx of hyperphosphatemia
4. reduce efficacy of FQs, tetracyclines (chelates), ketoconazole (dec abs in alkaline pH), digoxin, isoniazid, iron salts

Front 2

Antacids:onset, DOA, neutralizing capacity and SEs
1. NaHCO3
2. CaCO3
3. Mg(OH)2
4. Al(OH)3

Back 2

1. fast onset, short DOA, high NC; milk alkali, Na/H2O retention, metabolic alkalosis
2. fast onset, long DOA, high NC; diarrhea, accum
3. slow/mod onset, short DOA. low NC; C/D, milk-alkali, rebound hyperacidity
4. slow onset, long DOA, low NC; constipation, accum, hypophosh, osteomalacia, encephalopathy

Front 3

Simethicone
1. MOA
2. uses
3. toxicity

Back 3

1. relieves gas in GI by a defoaming action
2. combined w/ antacids to defoam gastric juice (dec GERD, no change in ANC)
3. inert and devoid of toxicity

Front 4

H2 Receptor Antagonist
1. MOA
2. metabolism
3. uses
4. SEs
5. unique cimetidine SEs

Back 4

1. selectively inhibits H2 > dec histamine release > dec H+/K+ ATPase > dec gastric acid secretion
2. largely renal (adjust for renal fxn)
3. GERD, ulcers, Zollinger-Ellison, HB/AI/SS
4. overall incidence is low: HA, nausea, dizziness, myalgia, rash, TCP, neutropenia, brady (IV), somnolence and confusion (more in elderly and renal insuff)
5. inc serum Cr, impotence, dec libido, gynecomastia, breast tenderness, CYP inhibitor

Front 5

Proton Pump Inhibitors
1. MOA
2. examples
3. uses
4. SEs
5. drug interactions
6. omeprazole specific SEs

Back 5

1. prodrug activated in acidic environment to irreversibly bind/inhibit H+/K+ ATPase
2. omeprazole, lansoprazole, rabeprazole, pantoprazole, esomeprazole
3. werosive esophagitis, H. pylori, gastric ulcer (O, L), duod ulcer (O, L, R), ZES ( O, L, R)
4. N/D, HA, somnolence, rash, leukopenia, inc LFTs
5. dec absorption of ketoconazole (needs acidic environment)
6. inhbiits CYP (will prevent activation of anti-platelet clopidogrel)

Front 6

Misopristol
1. what is it?
2. MOA
3. uses
4. SEs

Back 6

1. prostaglandin analog (PGE-1)
2. inhibits secretion of gastric acid and stimulates secretion of mucus and bicarb
3. prevention of NSAID induced gastric ulcers, labor induction, abortion (w/ mifepristone)
4. abortifacient (black box), diarrhea, abdominal pain

Front 7

Sulcralfate
1. what is it?
2. MOA
3. uses
4. SEs

Back 7

1. aluminum complex of sucrose sulfate; acts like band-aid
2. forms sticky cross-linked gel in acidic environment (pH<4) that adheres to ulcerated epithelium (protects for >6hrs); adsorbs pepsin; stimualtes PG synthesis
3. FDA approved for gastric and duod ulcer and postponing ulcer relapse
4. constipation, dry mouth, hypophosphatemia, accum (renal insuff), many drug interactions

Front 8

Bismuth Compounds
1. use
2. MOA

Back 8

1. enhances defensive factors in tx of acid peptic diseases
2. cytoprotective, inhibits pepsin, accumulates in ulcer crater

Front 9

Treatment of H. pylori Peptic Ulcers
1. suggested regimen
2. anti-secretory agents
3. antibiotics

Back 9

1. one anti-secretory agent and 2 antibiotics
2. ranitidine (2wk tx), PPI (2wk), H2 antag (4 wk)
3. cliarithromycin, amoxicillin, metronidazole, tetracycline (may combine bismuth with T and M)

Front 10

Bulk Forming Laxatives
1. examples
2. MOA
2. SEs

Back 10

1. Bran, Psyllium preparations, Cellulose, Polycarbophil
2. indigestible polysaccharides and cellulose derivative that absorb water; increase bulk/promote peristalsis
3. fecal impaction, intestinal obstruction, Na/water retention

Front 11

Emollient Laxatives
1. examples
2. MOA
3. SEs

Back 11

1. docusate Na/Ca/K
2. acts as a surfactant (emulsifies aqeuous and fatty substances w/ fecal matter) to soften stool
3. cramping, nausea

Front 12

Lubricant Laxatives
1. examples
2. MOA
3. SEs

Back 12

1. mineral oil
2. coats stool with oil to allow easier passage
3. fat soluble vitamin malabsorption, anal pruritis, aspiration pneumonia

Front 13

Saline Laxatives
1. examples
2. MOA
3. SEs

Back 13

1. Mg sulfate, Mg hydroxide, Mg citrate, Na Phosphate
2. increases osmotic pressure > water retention
3. electrolyte imbalances (inc MG, inc phosph, dec Ca, dec K

Front 14

Stimulant Laxatives
1. examples
2. MOA
3. SEs

Back 14

1. cascara, senna, phenolphthalein, bisacodyl, castor oil
2. irritation increases motility, inhibits absorption, enhances secretion
3. cramps, colonic discoloration, rash

Front 15

Hyperosmotic laxatives
1. examples
2. MOA
3. SEs

Back 15

1. lactulose, sorbitol, glycerin, PEG-electrolyte solutions
2. osmotic retention of water in intestinal lumen, local irritant effect stimulates evacuation
3. irritation, burning, cramping

Front 16

Opioid Agonist Anti-Diarrheals
1. MOA
2. examples

Back 16

1. act on mu and delta opioid receptors to dec motility and secretion > slows intestinal transit > inc Na/H2O absorption, dec secretion, inc rectal sphincter tone, dec peristaltic motion
2. diphenoxylate + atropine (atropine discourages abuse and dec motility), Loperamide (Imodium)

Front 17

Bismuth Subsalicylate
1. MOA
2. use
3. SE
4. OTC

Back 17

1. adsorbs bacterial toxins, local anti-inf
2. traveler's diarrhea, mild diarrhea
3. black stools, salicylate toxicity
4. pepto-bismol

Front 18

Octreotide
1. what is it?
2. MOA
3. uses
4. dosing

Back 18

1. somatostatin analogue
2. inhibits gastric acid, pepsinogen, and gastrin; decreases smooth muscle contractility
3. tx of refractory diarrhea (AIDS, DM), GI tumor causing diarrhea, other motility disorders
4. SQ

Front 19

5HT3 Receptor Antagonists
1. examples
2. use
3. MOA
4. SEs

Back 19

1. odansetron, granisetron, dolasetron
2. anti-emetic
3. antagonizes 5HT3 receptors in CTZ and upper GI tract
4. diarrhea, HA, fatigue, arrhythmias (dolasetron)

Front 20

Dopamine (D2) Receptor Antagonist
1. examples
2. use
3. MOA
4. SEs

Back 20

1. metoclopramide, prochlorperazine, promethazine, chlorpromazine, haloperidol, droperidol
4. SEDATION, anticholinergic, movement disorders, hypotension

Front 21

Other Agents Used as Anti-Emetics (besides 5HT3 and D2 receptor antagonists)

Back 21

1. corticosteroids
2. cannabinoids
3. benzodiazepines (anticipatory N/V)
4. antihistamine/antimusc (used in combo w/ D2 to reduce SE, motion sickness/vertigo)

Front 22

Metoclopramide
1. MOA
2. uses
3. Pk (distribution, metabolism)
3. SEs

Back 22

1. prokinetic agent: dopamine antagonist (inc motility of smooth mm, accelerates gastric emptying)
2. nausea (central dopamine antagonist), prokinetic (peripheral dopamine antagonism)
3. can cross BBB, renally excreted (adjsut dose for renal fxn)
4. EPS (worsens parkinsons)restlessness, drowsiness, fatigue, D/C

Front 23

Other Prokinetic Agents
1. Erythromycin
2. Cisapride
3. Domiperidone

Back 23

1. motilin agonist (stimulates gastric emptying and postprandial gastric contraction) for diabetic gastroparesis
2. no longer used due to arrhthmias and EKG problems
3. derivative of metoclopramide (invesetigational), dopamine antagonist that inc GI motility and can cause hyperprolactinemia

Front 24

Tegaserod maleate
1. MOA
2. use
3. SE

Back 24

1. activates 5-HT4 receptors in GI tract (inc motility, dec visceral sensation)
2. short-term tx of women with constipation predominant IBS
3. transient diarrhea

Front 25

Alosetron
1. MOA
2. use
3. SE
4. black box warning

Back 25

1. 5-HT3 receptor antagonist (dec motility)
2. diarrhea-predominant IBS in women
3. CYP interactions, dose-realated constipation
4. constipation leading to bowel obstriction/impaction/perforation/toxic megacolon/death (taken off market then reintroduced with lower dose and consent form)