GI, CNS Flashcards
antacids
Aluminum Hydroxide - Amphojel
Calcium carbonate - tums - ADR calcium products: hypercalcemia
Calcium carbonate w/ magnesium hydroxide - Rolaids
Magnesium Hydroxide - xind magnesium products: poor renal fxn pts, can lead to diarrhea
Sodium bicarbonate - alka seltzer - can exacerbate HTN/HF - hypernatremia/fluid overload
ADR all - may affect absorption of other medications - alters gastric pH, 1 hr between antacids and other substances
cimetidine
H2 Blockers - 65% decrease in acid secretion
OTC - no longer recommended
liver enzyme inhibitor - many interactions! raises levels of many other drugs phenytoin (szr med), warfarin
crosses BBB - can alter mental status - esp in older adults w/ renal fx
binds to androgen receptors - gynecomastia, reduced libido, and impotence
we now have new, safer H2blockers
famotidine
newer H2 Blocker
Fewer ADRs
Do NOT inhibit liver enzymes
Do not easily cross BBB
No antiandrogenic effects
omeprazole/pantoprazole
PPI - 90% decrease in acid secretion
for ulcer/ulcer pain - should be taken 30 min to 1 hr prior to eating (usually b4 breakfast)
ADRs - long term treatment - pneumonia, osteoporosis(decreases abs Ca), rebound hypersecretion, hypomagnesemia, gastric cancer
Sucralfate
mucosal protectant - forms a gel that coats stomach lining/ulcer - PUD
not helpful in treatment of GERD
nonabsorbable, does not affect acid secretion
misoprostol
analog of prostaglandin (stimulate secretion of mucus and bicarb, promotes vasodilation)
especially approved - prevention of NSAID related ulcer
caution in pregnancy - can cause miscarriage
H. pylori treatment
antibiotics treatment of choice - need more than 1 (2-3) (clarithromycin, amoxicillin, metronidazole, bismuth, tetracycline)
plus an antisecretory agent PPI/H2blkr
associated with gastric cancer - trtmt reduces adenocarcinoma
lifestyle modification - PUD
Avoid foods that exacerbate sx (no longer rec bland diet or caffeine elimination)
Alcohol in moderation
Smoking discouraged
Avoid NSAIDs
ondansetron - serotonin 5HT3 receptor antagonist
MOA: Blocks the serotonin receptor in the CTZ, as well as the intestinal wall and stomach - works in CNS and stomach
most effective drug available for suppressing N/V
admin: under the tongue (sublingual disintegrating), IV, PO
EKG -Risk for prolongation of QT Interval - can lead to ventricular dysrhythmias
other adrs: HA, dizziness, drowsiness, diarrhea - most common with repeated dose
haloperidol
antiemetic - dopamine antagonist- butyrophenone
FGA
ADRs: Extrapyramidal (EPS), Sedation, Hypotension, NMS
Associated with Fatal Dysrhythmia-prolong QT √ ECG - pre and during dosing
droperidol
antiemetic - dopamine antagonist - butyrophenone
stronger sedative than haloperidol
ADR - respiratory depression - BBW - intubation,
metoclopromide
Antiemetic - dopamine antagonist
MOA: blocks dopamine receptor & prokinetic - gastric emptying
ADR: sedation and diarrhea, ask GI hx xindic - GI beed, obstruction, perforation
may cause EPS
promethazine (phenergan)
Antiemetic - type - dopamine antagonist - Phenothiazines -
xind - peds + elderly - respiratory depression
ADR: sedation (leading to srs resp depression)
IV - vessicant - tissue necrosis from infiltration
Cannabinoid - dronabinol
Nabilone
MOA: Activates cannabinoid receptor in CTA
USE: CINV
Also appetite stimulate: CA, HIV/AIDS or adjunctive pain med
Active ingredient found in marijuana
ADR: Can produce the same subjective effects identical to those caused by smoking marijuana
Drowsiness, dizziness, impaired cognition, euphoria…
avoid alcohol other CNS depressants
pts that use a lot of MJ can require more opioids
Aprepitant
Neurokinin antagonist - blocks neurokinin-type receptors in the CTZ
delayed effectiveness - added to ondansetron for additional
ADR - fatigue
lorazepam
benzodiazepine
MOA: Enhance GABA Three benefits of Benzodiazepines in the treatment of N/V:
-Sedation
-Suppression of anticipatory nausea/vomiting
-Produces anterograde amnesia
-loss of ability to create “new” memories
Use: Frequently in combination with other antiemetics for CINV
methylprednisolone/dexamethasone
used off label for CINV
combo treatment - dexamethasone + substance P/N1 antagonist (aprepitant) or 5HT antagonist
dronabinol
MOA: Activates cannabinoid receptor in CTA
USE: Chemotherapy-induced N/V
Also appetite stimulate: CA, HIV/AIDS or adjunctive pain med
Active ingredient found in marijuana
ADR: Can produce the same subjective effects identical to those caused by smoking marijuana
Drowsiness, dizziness, impaired cognition, euphoria…
Should avoid alcohol and other CNS depressants
Schedule III drug
dymenhydrinate/diphenhydramine
antihistamines
anticholinergic s/e, sedation, xind: glaucoma
30min-1hr before activity
scopolamine
best for motion sickness
behind ear - 4 hr b4 activity
anticholinergic side effects - xind: glaucoma
Diphenoxylate with Atropine
opioid - only indic. is diarrhea
schedule V - controlled (added atropine - anticholinergic (dry mouth, urinary retention) - deterrent for abuse)
Loperamide
Analog of meperidine (synthetic opioid)
No narcotic or analgesic effect - does not cross BBB
Not regulated under the controlled substance act
(immodium)
ciprofloxacin
traveler’s diarrhea - most common cause - E coli, loperamide may also be used (may prolong infection/delay progression)
bismuth subsalicylate
pepto bismol
ADR: may cause black stools,
excessive use - ringing in the ears (contains derivative of aspirin - if taken with aspirin could start having sx of aspirin toxicity - ringing in ears)
Polycarbophil/methycellulose/psyllium
bulk forming laxatives
Natural fibrous substance - promote large, soft stools
MOA same as dietary fiber - indigestible/nonabsorbable
first line treatment - reduces risk of colon cancer
ADRs: can solidify in the GI –> obstructions with insuff fluid intake
xindic- people who cannot drink lots of fluid (HF)
Docusate Sodium/Calcium
Surfactant Laxative -
MOA - inc intestinal fluid secretion & inhibits fluid absorption - retain fluid in stool
considered “lubricants” and “stool softeners”
often rx’ed with opioids
prophylaxis - p/s MI, surgery, vaginal delivery
beneficial for elderly who cannot drink adequate fluids for bulk laxatives