GI Flashcards
Antacid indications
Hyperacidity, Peptic Ulcer Disease, GERD, Hyperphosphatemia, Calcium Deficiency
Antacid precautions/contraindications
abdoominal pain of unknown case
renalcalculi avoid
calcium containing antacids
renal failure avoid
magnesium based antacids
what is strongly cautioned against with renal failue
aluminum
sodium content in antacids may affect patients with
HTN, CHV, or renal failure
Adverse drug reactions - Antacids aluminum and calcium based
consipation
Adverse drug reactions - Antacids magnesium based
diarrhea
Antacid administration with other drugs need to be seperated by
at least two hours
Antacid you should always do what first
find the underlying cause
Combination products have the highest
acid neutralizing capcity
docum content of antacid is
listed on the lable.
monitoring for antacids
Magnesium level in older patients who use magnesium-containing products chronically
provide ___ ___ for people taking antacids
Provide lifestyle chainage education - Stop smoking, elevate head while sleeping, and avoid spicy foods, alcohol, or foods that affect lower esophageal sphincter tone (fatty foods, chocolate, caffeine).
Anti-diarrheal three classes
absorbent preparations
Opiates
Anti-cholinergics
Kaolin
clay like powder that attraches and holds onto bacteria - anti-diarrheal
pectin
thinkens stool
bismuth sulfate
anti secretory and anti microbial effects
Examples of opiates
loperamide (Imodium) (binds to opioid receptors and slows gastric motility), diphenoxin with atropine (Motofen), diphenoxylate (opioid) with atropine (Lomotil)
anti-cholinergics are only useful in
IBS
Kaolin and pectin are not
absorbed and are eliminated in feces.
Bismuth subsalicylate dissociates into
into salicylate that is absorbed (similar to aspirin), metabolized in the liver, and excreted in urine with the bismuth that is not absorbed.
The opioid agents are all absorbed and distributed …
systemically, metabolized in the liver, and eliminated in urine and/or feces.
Opioids decrease __ and cause __
intestinal motility and may cause toxic megacolon.
Bismuth subsalicylate is contraindicated
contraindicated in children with viral or flu-like illness. similar to given asprin. reyes syndrome
Anti-dirrheals use caution in
older adults
antidiarrheal are contraindicated in the
treatment of diarrhea in most children.
Most common drug interaction with anti-diarrheals
constipation, dark stools with bismuth sulfate (warn patients of this)
Diphenoxylate and difenoxin with atropine: have
have anticholinergic effects
Drug interactions – Anti-diarrheals
Aspirin, insulin, CNS depressants
Anti-diarrheals - culture stool
when appropriate (diarrhea lasting more than 7-10 days) and treat infection appropriately
Most infectious diarrhea is
self limiting – from viruses or other bacteria. However, severe bacterial infections such as Salmonella, C Diff, Shigella etc. must be treated with antibiotics. Example traveler’s diarrhea.
KEY to treatment of diarrhea is to
KEY to treatment of diarrhea is to
Cytoprotective Agents example
sucralfate and misoprostol
Sucralfate MOA
coats the lining/coats the ulcer to create a barrier to acid, pepsin and bile salts
Technically topical in how it works, very safe, safe in pregnancy
Misoprostol – inhibits
basal and nocturnal acid secretion also has protective qualities for mucosal lining
MIsoprostol is contraindicated in and use with caution in
Contraindicated in pregnancy! May cause abortion or premature birth or birth defects.
Caution in renal patients
Cytoprotective Agents - ADR
Sucralfate: constipation
Misoprostol: diarrhea, menstrual problems (CHECK pregnancy test in women of childbearing age)
Cytoprotective Agents - Interanctions
Sucralfate: decreases absorption of other drugs
Misoprostol: diarrhea with magnesium-containing antacids
Cytoprotective Agents - Clincial indications
Ulcers associated with NSAID use (first step stop NSAIDs)
Duodenal ulcers (sucralfate up to 8 weeks t heal ulcer, give up to 4 times a day, 1 hour before meals)
Antihistamines (first generation) - MOA
Antiemetic
Have strong anti-cholinergic effects and histamine 1 blocking effects
Phenothiazines
Phenothiazines MOA
Antiemetic
Block dopamine receptors in the chemoreceptor trigger zone
Cannabinoids MOA
Antiemetic
Work in the central nervous system (CNS) to prevent nausea and vomiting associated with cancer chemotherapy
5HT3 Antagonists MOA
Antiemetic
Block serotonin on vagal nerve terminals and in the chemoreceptor trigger zone
Sustance P/NK receptor antagonist MOA
Antiemetic
The emetogenic effects of substance P are mediated through the neurokinin-1 (NK1) receptor, a member of the G protein receptor superfamily
Phenothiazines
Produce
extrapyramidal symptoms (EPS)
Phenothiazines - contraindicated in
parkinson’s disease
dronabinol use with caution in patients with
seizure disorder
5-Ht3 receptor antagonists
may mask progressive ileus
