Gi Drugs

Front 1

Calcium carbonate

Back 1

Class - nonsystemic Antacid
Indication - PUD, reflux esophagitis
SE, Tox - hypercalcemia (esp. with dairy products), renal stones, Ca stimulates secretion of gastrin and HCl --> acid rebound

Front 2

Aluminum hydroxide

Back 2

Class - nonsystemic Antacid
Indications - PUD
SE, Tox - *constipation*, hypophosphatemia, proximal myopathy, encephalopathy in pts on dialysis

Front 3

Magnesium salts

Back 3

Class - nonsystemic Antacid
Indication - PUD
SE, Tox - *diarrhea*, milk-alkali syndrome with dairy products, metabolic *alkalosis* esp. in renal insufficiency. exacerbation of CHF, edema because of sodium intake.
CI - HTN

Front 4

Antacids

Back 4

All can cause hypokalemia.

Front 5

Cimetidine

Back 5

Class - H2 blockers (block parietal cell histamine receptors)
Indications - Tx/prevent PUD, ZE, gastritis, mild GERD
Properties - acid secretion inhibited for 4 hours
SE, Tox - only H2 blocker to inhibit P450 system --> increase serum levels of EtOH, warfarin, digitoxin, TCA, phenytoin, carbamazepine, β-blockers, benzos. antiadrogenic, decreased renal excretion of creatinine.

Front 6

Ranitidine

Back 6

Class - H2 blockers (block parietal cell histamine receptors)
Indications - Tx/prevent PUD, ZE, gastritis, mild GERD
Properties - more potent than cimetidine. 1-2x daily.
SE, Tox - less than cimetidine, doesn't penetrate CNS as much, no P450 effect.

Front 7

H2 Blockers

Back 7

cimetidine, ranitidine, famotidine, nizatidine

Front 8

Omeprazole, Lansoprazole

Back 8

Class - PPI
Indications - GERD, PUD, ZE, gastritis. esp. when refractory to H2 blockers.
Properties - irreversible inhibition, prodrug that diffuses into acid space of secretory canaliculus where it is protonated to active form.
SE, Tox - overgrowth of bacteria

Front 9

Sucralfate

Back 9

Indications - PUD
Properties - activated in acid environment. negative charges bind to positively-charged proteins in ulcerated tissue. Provides physical protection.
SE, Tox - minor. mostly constipation. decrased absoprtion of ciproflaxin, norflaxin. because it needs acid to be activated, do not give with antacids, H2 blockers, PPIs.

Front 10

Bismuth

Back 10

Indications - PUD
Properties - binds to ulcerr providing physical protection. possible antimicrobial activity against H. pylori.

Front 11

Misoprostol

Back 11

Class - PGE₁ analog
Indications - prevent gastric ulcers caused by NSAIDS.
SE, Tox - Diarrhea.
CI - potentially childbearing women (induces labor).

Front 12

Antibiotics for PUD

Back 12

Tetracycline, Metronidazole, Clarithromycin, plus H2 blocker drastically reduces recurrence compared to H2 blocker alone.

Front 13

Ipecac

Back 13

Class - Emetic
Properties - irritates GI tract, stimulates chemoreceptor zone. Onset = 15-30 min.

Front 14

Prochlorperazine, chlorpromazine, metoclopramide

Back 14

Class - Dopamine receptor antagonists.
Properties - Act at D2 receptors at chemoreceptor trigger zone --> antiemesis.

Front 15

Ondansetron

Back 15

Class - Antiemetic
Properties - 5-HT3 antagonist
Indications - control vomiting postop and during chemotherapy.
SE, Tox - headache, constipation.

Front 16

Bulk-forming Laxatives

Back 16

Examples - dietary fiber, semisynthetic polysaccharides/cellulose (methylcellulose).
Properties - osmotic effect --> fluid/electrolyte renetion in intestinal lumen. increased fecal mass/softness --> accelerated transit. Works within 1-3 days after PO administration.
Indications - diverticular disease, IBS.
SE, Tox - flatulance, electrolyte imbalances, esophogeal/intestinal obstruction therefore take with fluids

Front 17

Castor Oil

Back 17

Class - Stimulant laxative
Properties - hydrolyzed in small intestine to active ingredient --> decreased reabsorption of electrolytes/fluids and stimulates peristalsis. works within 1-3 hours after PO administration.
SE, Tox - chronic use impairs absorption of essential nutrients, excacerbates dehydration and electrolyte disturbances.

Front 18

Bisacodyl

Back 18

Class - Stimulant laxative
Properties - onset of action (oral) = 6-12h, (rectal) = 1h.
SE, Tox - fluid/electrolyte deficiencies, rash, rectal burning

Front 19

Anthroquinones

Back 19

Class - Stimulant Laxative. (cascara and senna, eg)
Properties - effect at large intestine. Increase peristalsis.

Front 20

Docusates

Back 20

Class - Stimulant Laxative
Properties - anionic surfactant. Softens stool by emulsifying water, fat, and feces. Onset of action = 1-3d.
Indications - used after abdominal surgery and postMI.
SE, Tox - nausea, cramping. Don't use with mineral oil.

Front 21

Salt-containing Osmotic Laxatives

Back 21

Properties - contain Mg, phosphate, sulfate salts. fluid retention --> increased motility. Onset of action = 2h, semifluid stools.
Indications - bowel evacuation prior to surgery/imaging.
SE, Tox - Mg salts --> hypermagnesemia in pts with renal insufficiency. Na salts exacerbate CHF, cause dehydration.

Front 22

Lactulose

Back 22

Class - nonsalt Osmotic Laxative
Properties - semisynthetic disaccharide. Traps ammonia as NH4+, enhances excretion of nitrogenous wastes in hepatic insuffiency. Onset of action = 1-3d.
Indications - laxative and in hepatic encephalopathy
SE, Tox - N/V, flatulence, diarrhea, dehydration, hypokalemia.

Front 23

Mineral Oil

Back 23

Class - Surfactant Laxative
Properties - softens stool
SE, Tox - limiting. pneumonitis after aspiration, imparied absorption of fat-soluble nutrients, pruritus ani (ew.)

Front 24

Loperamide

Back 24

Class - Opiate
Indications - Diarrhea
Properties - since it poorly crosses BBB, it has few side effects and low potential for abuse. decreases GI motility.

Front 25

Infliximab

Back 25

Class - monoclonal Ab to TNF-α (a proinflammatory cytokine)
Indications - Crohn's Disease, rheumatoid arthritis.
SE, Tox - respiratory infection, fever, hypotension

Front 26

Sulfasalazine

Back 26

Class - combo of sulfapyridine (antibacterial) and mesalamine (anti-inflmmatory).
Indications - Ulcerative colitis, Crohn's disease
SE, Tox - Malaise, nausea, sulfonamide toxicity (hypersensitivity rxn, hemolysis in G6PD deficient pts, nephrotoxicity, kernicterus, displacing drugs (warfarin) from albumin)