Pud

Front 1

General Mechanism of action for Antacids

What are the agents mentioned?

Back 1

Principle action: decrease intra-gastric acidity.

May stimulate prostaglandins and increase mucus secretion.


NaHCO3 [Baking soda, alka-seltzer]
CaCO3 [Tums, Os-Cal]
Mg(OH)2 or Al(OH)3 [Maalox, Mylanta
Rapid relief, Short acting.

Front 2

NaHCO3 actions and adverse effects

Back 2

Rapidly forms CO2 and NaCL

#1 issue: CO2 can cause gastric distention and belching
NaCl can exacerbate fluid retention. NaHCO3 that is unabsorbed can cause METABOLIC ALKALOSIS

Front 3

CaCO3 actions and adverse effects

Back 3

Rapidly forms CO2 and CaCl2, slower than NaHCO3.

Adverse: bleching, metabolic alkalosis, milk alkali syndrome

**Can cause gastric hypersecretion and acid rebound so it it not a good choice for peptic ulcer disease**

Front 4

Milk-Alkali Syndrome

Back 4

Due to ingestion of Calcium and absorbable alkali. Pt's were given CaCO3 w/ milk or cream and could develop Hypercalcemia, renal insufficiency

Front 5

Mg(OH)2 and Al(OH)3 actions and adverse effects

Back 5

Slower acting, lasts longer. Mg2+ salts cause diarrhea, Al3+ salts cause constipation.

*****C/I in renal insufficiency!***

Front 6

Do not give antacids w/in two hours of ________

Back 6

Tetracycline, Fluoroquinolones, itraconazole, and Iron. Antacids affect the abosrption.

Front 7

What are the two actions of H2-Receptor Antagonists

And what are the 4 agents mentioned?

Back 7

1. Block Histamine binding to parietal cells and reduces activation of parietal cells.
2. Reduced cAMP levels in Parietal cells resulting in attenuated response to ACh and Gastrin.

**H2-Receptor Antagonists are effective for nocturnal acid reduction significant in duodenal ulcers

Cimetidine, Ranitidine, Famotidine, Nizatidine

Front 8

Clinical uses of H2-receptor antagonists:

Back 8

1. Peptic Ulcers, nocturnal dosing for uncomplicated gastric/duodenal ulcers. 2nd line for H. pylori
2. GERD, 2nd line, given 30-60 min before meals
3.Dyspepsia: common OTC
4.Bleeding from gastric related gastritis:
5. Warts: **Cimetidine effective as alternative therapy for viral warts
6. Tolerance**** can develop due to H2 blocks and a REBOUND increase in gastric acididty occurs after discontinuation.*****

Front 9

Adverse effects of H2-Receptor Antag's

Back 9

Common: diarrhea, headache, fatigue, myalgias, constipation

Less Common:
CNS: confusion (elderly pt's). ****Cimetidine can inhibit binding of dihydrotestosterone causing increased estradiol/prolactin causing gynecomastia/impotence in males and galactorrhea in women.
Also, block H2 receptors in heart causing bradycardia/hypotension w/ rapid infusions

Front 10

Drug interactions of H2-Receptor Antag's?

Back 10

Antacids will decrease absorption of H2 antagonists.

Know that Cimetidine has SIGNIFICANT drug interations.

Also: **all H2 blockers (except famotidine) inhibit 1st pass metabolism of ethanol

Front 11

What are the 5 proton pump inhibitors mentioned in class?

Back 11

Omeprazole, Lansoprazole, Rabeprazole, Pantoprazole, and Esomeprazole

PPI's are 1st choice for PUD

Front 12

Mechanism of Action of PPI's?

Back 12

Prodrugs. They are weak bases and are protaonated in highly acidic canaliculus of parietal cell. Here they are converted to active, reactive thopilic sulfonamide cation which irreversibly blocks ACTIVE H+/K+ ATPases.

Net effect is direct/long lasting reduction of resting/active gastric acid secretion.

Front 13

What makes PPI's ideal drugs for PUD?

Back 13

*short serum half-life and long duration
*Concentrated and activated near site of action
*Specific
*Inhibit fasting and active secretion

Must be administered 1 hour before eating

Front 14

Clinical Uses of PPI's?

Back 14

Agents of choice for most acid peptic disorders

*Gerd: most effective agent, long term therapy needed.

Peptic Ulcer Disease: heals 90% of duodenal Ulcers and Gastric Ulcer. ***First line treatment for H. Pylori infections. Effective for NSAID ulcers.

Nonulcer Dyspepsia: others are better

Used in stress gastritis and Zollinger Ellison.

Front 15

Adverse effects of PPI's

Back 15

Diarrhea, headache, abdominal pain. *Hypergastrinemia is more severe and frequent that w/ H2 blocks. Pt's show a reduction in Cobalamin absorption*. This is also increased enteric infections and aspiration pneumonia

Increased gastrin can lead to gastric carcinoma and Colon cancer.

NO indications of longterm cardiac risks

Front 16

Drug interactions of PPI's

Back 16

Drugs relying on gastric acid for absorption will have decreased activity (Ketoconazole and Digoxin)

Front 17

What are the three Mucosal Protective Agents mentioned?

Back 17

Prostaglandin Analogs

Sucralfate

Colloidal Busmuth Compounds

Front 18

Actions of Prostaglandin analogs

Back 18

Bind to parietal cells causing modest reduction in acid secretion. Binds to epithelial cells stimulating mucus and bicarbonate secretions. Increase mucosal blood flow.

Front 19

Misoprostol (cytotec): uses/adverse

Back 19

Sythetic analog of PGEI. Can stimulate intestinal electroly, fluid secretion, motility and UTERINE CONTRACTIONS

Uses: not widely used. Combo w/ Diclofenac (NSAID) for arthritis. Used to terminate pregnancies as well

Adverse effects: Diarrhea/cramping. CONTRAINDICATED IN PREGNANCY

Front 20

Sucralfate:

Back 20

Not used much, can be used for Duodenal Ulcers

MOA: reacts w/ HCl to form paste that binds to damaged GI mucosa.

Minimal adverse effects, take on empty stomach

Front 21

Colloidal Bismuth Compounds

(Bismuth Subsalicylate)

Back 21

Reduces stool frequency and liquidity in acute diarrhea by inhibiting prostaglandins and chloride secretion in intestine.

Also has direct antimicrobial effect

Adverse: blackening of stool, darkening on tongue