Choi Pharm Flashcards
Drugs for Acid-Peptic Dz
Agents that reduce intra-gastric acidity:
1. antacids-
NaHCO3, Ca carbonate, Mg hydroxide, Al hydroxide
2. H2 antagonists( -dine)-
cimetidine, ranitidine, nizatidine, famotidine
3. PPI (-zole)-
omeprazole, esomeprazole, lansoprazole, dexlansoprazole, rabeprazole, pantoprazole
Agents that promote mucosal defense:
sucralafate, misoprostol, bismuth compound
Sodium Bicarbonate (baking soda, alka seltzer)
Antacid Can cause: CO2 gas - distention, belching metabolic alkalosis Na - fluid retention
Calcium carbonate (tums)
Antacid Can Cause: -CO2 gas - distention, belching -metabolic alkalosis -Milk alkali syndrome when taken with milk (hypercalcemia, renal insufficiency, metabolic alkalosis)
Magnesium hydroxide
Antacid
Can Cause:
-osmotic diarrheagiven in combo with aluminum hydroxide (maalox)
Aluminum Hydroxide
Antacid
Can Cause:
-constipation
-given in combo with magnesium hydroxide (maalox)
Complications of Antacids
- pts with renal insufficiency should not take long term
- affects absorption of other medications (should not be taken within 2 hours of tetracyclines, fluoroquinolone, itraconazole, and iron)
H2 antagonists
Cimetidine, Ranitidine, Nizatidine, Famotidine
-Best for nocturnal acid secretion
Adverse effects of cimetidine:
- gynecomastia
- inhibits CYP1A2, CYP2C9, CYP2D6, and CYP3A4 (negligible with nizatidine and famotidine)
PPI’s
Omeprazole, Esomeprazole, Lansoprazole, Dexlansoprazole, Rabeprazole, Pantoprazole
- prodrugs
- antagonize meal-stimulated and nocturnal acid secretion
- very short half-life but long duration of action (covalently bind)
- Should be taken 1 hour before meal and for a few days for full affect
Adverse effects:
- decreased B12 levels with prolonged therapy
- increased hip fractures
- life threatening hypomagnesemia with secondary hypocalcemia (black box warning)
- increased risk of both community-acquired respiratory infections and nosocomial pneumonia
- increased risk of enteric infections
- potential problems due to increased serum gastrin
*should not be given with clopidogrel
Triple Therapy
clarithromycin+metronidazole+PPI
Quadruple Therapy
PPI+metronidazole+bismuth cpmd+tetracycline
Sucralafate
Promote Mucosal Defense
- physical barrier and stimulates mucosal PG and HCO3 secretion
- prevention of stress
- related bleeding in critically ill pts
Adverse effects:
-Constipation
Misoprostol
Promote Mucosal Defense
- PGE1 analog
- Reduces histamine-stimulated cAMP production
- stimulates mucous and HCO3 secretion, enhances mucous blood flow
Clinical Uses:
-NSAID-induced ulcers
Adverse effects:
-diarrhea, cramping, abdominal pain, stimulate uterine contrations (C/I in pregnancy)
Bismuth Compunds (pepto bismol)
- create protective layer, may stimulate PG, mucous, HCO3 secretion
- direct antimicrobial effects and binds enterotoxins
Clinical:
- dyspepsia, acute diarrhea, prevention of traveler’s diarrhea
- quadruple therapy
AE:
- black stool and darkening of tongue
- short-term use only, avoid in renal insufficiency
- prolonged usage may lead to bismuth toxicity resulting in ENCEPHALOPATHY (ataxia, HA, confusion, seizures)-salicylate toxicity
Prokinetic Dugs
Cholinomimetics, D2 antagonists, Macrolides
Bethanechol
Cholinomimetic
- stimulates M3
- used in past for tx of gastroparesis
Neostigmine
Cholinomimetic
- AChE inh.
- IV–> hosp. pts with acute large bowel distention (Ogilvie’s syndrome)
AE:
-excessive salivaiton, N/V, diarrhea, bradycardia
Metoclopramide (domperidone in other countries)
D2 antagonist
- D2 receptor inhibits cholinergic stimulation
- tx for diabetic gastroparesis, prevention of vomiting, postpartum lactation stimulation
AE:
- restlessness, drowsiness, insomnia, anxiety, and agitation
- EPS
- Tardive dyskinesia
- elevated prolactin
Erythromycin (as prokinetic)
Stimulates motilin receptors causing a MMC
-IV for gastroparesis, gastric emptying of blood in acute upper GI hemorrhage before endoscopy
Laxatives
- bulk forming
- stool softeners
- osmotic laxatives
- stimulant laxatives
- Cl channel activator
- opiod receptor antagonists
- 5HT4 agonists
- Guanylate cyclase C agents
Bulk forming laxatives
psyllium, methylcellulose, polycarbophil
stool surfactant agents
ducosate and glycerin suppository
osmotic laxatives
magnesium hydroxide, sorbitol, lactulose, magnesium citrate, sodium phosphate, balanced polyethylene glycol
stimulant laxatives
aloe, senna, cascara, bisacodyl
Cl channel activator (laxative)
lubiprostone