Week 12 cont: GI Flashcards
Clarithromycin // Amoxicillin // Bismuth // Metronidazole // Tinidazole // Tretracycline: Class, Indication, MoA (2), AE (2)
Class: Antibiotics
Indication: PUD due to H. pylori
MoA:
- CANNOT be given alone, give with antisec agent
- Targets bacteria
AE:
- Increased risk of bacterial resistance (if given alone)
- -azoles: Disulfram-like reaction with alcohol
Cimetidine // Famotidine: Class (2), Administration, Indication, MoA (2), AE (3), Interactions (2)
Class:
- H2 receptor antagonist
- Antisecretory agent
Administration: PO, large Vd (including BBB)
Indication: PUD
MoA:
- Block H2 receptor in stomach
- Decreased gastric acid secretion
AE (RARE):
- Anti-androgenic: gynecomastia, impotence
- CNS effects: confusion, hallucinations, depression/excitation
- Pneumonia
Interactions
- CYP450 inhibitors
- Antiacids decrease absorption of cimetidine
Omeprazole // Iansoprazole // Pantoprazole: Class (2), Indication, MoA (2), AE (5), Interaction (1)
Class:
- Proton pump inhibitor
- Antisecretory agent
Indication: PUD
MoA:
- Prodrug
- Irreversible inhibition of H+/K+ ATPase
AE:
- Minor: HA, N/V, dirrhea
- Pneumonia
- Long term + high dose → fractures
- Rebound acid hypersecretion
- HypoMg2+
Interaction: Decreased absorption of some HIV drugs + antifungals
Antiacids: Indication, MoA (2), Contraindications (2)
Indication: PUD
MoA:
- Alkaline compounds neutralize stomach acid
- Minimal systemic absorption
Contraindications:
- Severe renal disease
- Heart failure
Sucralfate: Class, Administration, Indication, MoA (2), AE (1), Interaction
Class: Increases defensive factors
Administration: PO
Indication: PUD
MoA:
- In low pH, polymerization of drug occurs
- Sticky gel over ulcer
AE: Minimal constipation
Interaction: May decrease absorption of other drugs (give 2hr apart)
Misoprostol: Class (2), Indication, MoA (3), AE (3), Contraindication
Class:
- Increases defensive factors
- Prostaglandin E1 analog* Direct replacement for NSAIDs that inhibit PG
Indication: PUD
MoA:
- Suppresses gastric acid secretion
- Promotes secretion of bicarbonate + mucus
- Maintains submucosal blood flow
AE:
- Dose-related diarrhea
- Abdominal pain
- Spotting/dysmenorrhea
Contraindication: Pregnancy
Psyllium: Class (2), Indications (2), MoA (2), AE
Class:
- Bulk-forming laxative
- Type 3: slow → soft, formed stool
Indications:
- Constipation
- Diarrhea
MoA:
- Swell in water → increase in stool bulk
- Stretching of intestinal wall → peristalsis
AE: Minimal
Docusate: Class (2), Indication, MoA (2), AE
Class:
- Surfactant laxative (stool softener)
- Type 3: slow → soft, formed stool
MoA:
- Lower surface tension of stool = facilitation of H2O entry
- May also stimulate H2O + electrolyte secretion into intestinal lumen
AE: Minimal
Bisacodyl // Senna: Class (2), Administration (2), Indication, MoA (2), AE (1)
Class:
- Stimulant laxative
- Type 2: Intermediate → semifluid stool
Administration:
- PO
- PR (more rapid)
MoA:
- Stimulate intestinal motility
- Increase H2O + electrolyte secretion into intestinal lumen
AE: Cramping
Mg compounds // Polyethylene glycol // Lactulose: Class (2), Indication (2), MoA (2), AE (4)
Class:
- Osmotic laxative
- Type 1/2: rapid/intermediate → watery/semi-fluid stool
Indication:
- Constipation
- Lactulose: liver cirrhosis symptoms
MoA:
- Poorly absorbed compounds draw water into the intestinal lumen
- Increase fecal mass and peristalsis
AE:
- Dehydration
- Bloating
- Cramping
- Flatulence
Methylnaltrexone: Class, Indication, MoA (2)
Class: Opioid antagonist (selective mu)
Indication: Constipation
MoA:
- Blocks mu receptors on the GI tract
- Increases peristalsis
Ondansetron: Class, Administration, Indication, MoA, AE (4)
Class: Serotonin receptor antagonist
Administration: PO/IV
Indication: Antiemetic
MoA: Block 5-HT3 of CTZ and afferent GI neurons
AE:
- Headache
- Dizziness
- Diarrhea
- QT prolongation
Dexmethazone: Class, Administration, Indication, AE (2)
Class: Glucocorticoid
Administration: IV
Indication: Antiemetic
AE:
- No serious AE due to short duration
- Can see transient blood glucose increase
Aprepitant: Class, Administration, Indication, MoA, AE, Contraindications (2)
Class: SubP/NK1 receptor antagonist
Administration: PO
Indication: Antiemetic (cancer nausea prevention)
MoA: Block NK1 receptors in CTZ
AE: Well tolerated (some fatigue + dizziness)
Contraindications:
- Inhibits one family of CYP450, induces another
- Increase metabolism of warfarin and OCs
Phenothiazine (Promethazine): Class, Indication, MoA, AE (5), Contraindication
Class: Dopamine antagonist
Indication: Antiemetic
MoA: Block DA2 receptors in CTZ
AE:
- Hypotension
- Sedation
- Respiratory depression
- EPS
- Tissue injury with extravasion
Contraindication: <2yr
Butyrophenone (Haloperidol): Class, Indication, MoA, AE (6)
Class: Dopamine antagonist
Indication: Antiemetic
MoA: Block DA2 receptors in CTZ
AE:
- Hypotension
- Sedation
- Respiratory depression
- EPS
- Tissue injury with extravasion
- QT prolongation
Cannabinoids: Indications (2), MoA, AE (5)
Indications:
- Antiemetic
- Appetite stimulation in AIDS patients
MoA: Unknown (maybe agonism of cannabinoid receptors in vomiting center)
AE:
- Tachycardia
- Hypotension
- Drowsiness
- Abuse potential
- Caution with psych disease
Scopolamine: Class, Administration, Indication, MoA (2), AE (4)
Class: Muscarinic receptor
Administration: PO, SQ, transdermal
Indication: Antiemetic (prophylactically)
MoA:
- Block M receptors
- Decrease transmission from inner ear to vomiting center
AE:
- Dry mouth
- Blurry vision
- Drowsiness
- Urinary retention, constipation, disorientation (rare)
Meclizine: Class (2), Indication, MoA (2), AE (5)
Class:
- Antihistamine
- Muscarinic + histamine receptor antagonist
Indication: Antiemetic
MoA:
- Block M + H receptors
- Decrease transmission from inner eat to vomiting center
AE:
- Sedation
- Dry mouth
- Blurry vision
- Urinary retention
- Constipation
Lopramide: Class, Indication, MoA (4)
Class: Opioid
Indication: Nonspecific antidiarrheal
MoA:
- Activate opioid receptors
- Decreased bowel motility
- Allows for increased time for absorption of H2O and electrolytes
- COMBINE WITH OTHER DRUGS with unpleasant side effects to prevent abuse
Alosteron: Administration, Indication, MoA (3), AE (1), Contraindications (3)
Administration: PO, CYP450 metabolism
Indication: IBS-D in women
MoA:
-5-HT3 specific block
- Decreased abdominal pain
Increased colonic transit time
AE: Well tolerated, severe AE due to ischemic colitis
Contraindications:
- GI obstruction
- Constipation
- GI perforation
Sulfazalazine: Class, Indication, MoA (3), AE (4)
Class: 5-aminosalicylate
Indication: IBD
MoA:
- Metabolized by intestinal bacteria (5-ASA + sulfrapyridine)
- 5-ASA: suppresses PG synthesis + local inflammation
- Sulfrapyridine: AEs
AEs:
- N/V
- Rash
- Arthralgia
- Rare: agranulocytosis, hemolytic anemia
Budesonide: Class, Administration, Indication, MoA (2)
Class: Glucocorticoid
Administration: PO or IV
Indication: IBD (not long-term)
MoA:
- Releases drug when it reaches ileum and ascending colon
- Results in higher concentration where it’s needed with lower systemic effects (decreased inflammation)
Azathioprine // Cyclosporine // Methotrexate: Class, Indication, MoA, AE (3)
Class: Immunosuppressants
Indication: IBD (long-term)
MoA: Suppress immune response
AE:
- Bone marrow suppression, pancreatitis
- Renal impairement
- Neurotoxicity
