final exam lecture 5 Flashcards
Increase in intestinal motility leads to_____. Decrease un intestinal motility leads to_____
diarrhea, constipation
relationship between segmenting contractions and diarrhea
patients with diarrhea often have fewer spontaneous segmenting contractions
classifications of diarrhea
Acute, persistent, chronic, chronic idiopathic
difference between acute, persistent, chronic and chronic idiopathic
acute diarrhea <14 days (usually caused by infectious process)
persistent >14 days
chronic >30 days
chronic idiopathic >or equal to 4 weeks (persistently loose stool without identifiable cause)
chronic diarrheaaffects what percent of people
5%
most common foodborne cause of diarrhea and vomiting
Norovirus
What is fecal incontinence
Inability to control bowel movements, causing stool to leak unexpectadely
4 ways to classify diarrhea
Secretory
osmotic
exudative
altered intestinal transit
Secretory diarrhea mechanism? what does it cause?
Change in active ion transport causes water to move into the intestine. Causes large stool volumes (>1L/day). It does not improve with fasting
how is osmotic diarrhea caused? What does it cause?
It is caused when poorly absorbed substances are retained in intestinal fluids; resulting in influx of water. Causes lactose intolerance. Improves with fasting.
Exudative diarrhea define
Subset of diarrhea. secondary to inflammatory disease of the bowel. We see mucus, protein and blood in gut.
3 infectious organisms commonly associated with causing diarrhea
Bacteria (salmonella) most common bacteria in US), viral
viral- norovirus/ rota virus
common medications for drug induced diarrgea
Laxatives, metformin etc
complications of diarrhea
dehydration
electrolyte imbalance
evaluating a patient for dehydration
skin tenting, concentrated urine, dizziness when standing, dry mucous membrane
questions to ask patients regarding their diarrhea
When did symptoms begin
Frequency, consistency and color of stool
abdominal pain?
recent travel?
non pharmacologic treatment for diarrhea. What kind of diarrhea is it more important for?
BRAT diet (banana, rice, apple sauce, toast)
more important foo osmotic diarrhea
fluid- electrolyte replacement
Treatment if acute diarrhea (<3 days) with no fever or systemic symptoms
Symptomatic therapy
1) fluid/electrolyte
2) loperamide, diphenoxylate
3) diet
How to treat acute diarrhea with fever or systemic symptoms
Check feces for WBC/RBC/Ova and parasites.
If negative- symptomatic therapy.
If positive- use appropriate antibiotic therapy
treatment of chronic diarrhea
Always refer to physician
Give hydration and loperamide
how to prevent travelers diarrhea
drink bottled water
antimicrobial prophylaxis should not be used routinely
medicine to prevent travelers diarrhea
Bismuth subsalicylate
When is the only time we can use antimicrobial prophylaxis to treat travelers diarrhea? What antibiotic is recommended
Rifaximin is recommended. Only used for at risk populations.
Treatment for mild travelers diarrhea
Oral rehydration is used on ALL patients with travelers diarrhea.
Antibiotic use is not recommended
Loperamide or BSS may be considered
BSS dose: 60 ml or 2 tabs QID
Moderate travelers diarrhea treatment
Antibiotic MAY be used. Loperamide may be considered as monotherapy or adjunctive
Travelers diarrhea (severe)
Antibiotic treatment SHOULD be used. Single dose therapy preferred. Loperamide may be used as adjunctive therapy
How to treat drug induced diarrhea
Dx offending agent and use oral rehydration agents.
how do antimotility drugs treat diarrhea
They activate Mu opioid receptors on smooth muscle of the bowel to reduce peristalsis and increase segmentation
What are some concerns with antimotility drugs? name an antimotility drug
Should not be used long term and Not to be used with C.diff diarrhea.
Loperamide
loperamide doses
4 mg initially with 2 mg after each loose stool. Do not exceed 16 mg/day
how do anti secretory drugs treat diarrhea
act by reducing secretions in gut.
name an expample of antisecretory drugs
BSS (bismuth sub salicylate) (pepto bismol)
dosing of peptobismol? side effects?
2 tabs (30 ml) every 30-60 mins prn (upto 8 doses/24 hrs)
may potentiate anticoagulants, cause stools to turn black
Name 4 antimotility drugs. Maxdosing? OTC or RX? controlled sybstance?
Loperamide- do not exceed 8 pills a day, OTC
diphenoxylate/atropine (lomotil)- do not exceed 20 mg/day (4 pills), C V (RX ONLY)
Difenoxin/Atropine (motofen)- Not to exceed 8 tabs a day (CIV) Rx only1
Name an absorbent. DIarrhea or constipation? DOsing?
Psyllium (metamucil), 1-2 tsp mixed in 8 oz water 1-3 times a day
name some causes of constipation
Dietary
(Poor fluid intake, decreased caloric intake)
Disease states that slow down GI motility
(diabetes, Parkinsons, CNS injury)
Common drugs that cause constipation
Opioids (mu receptor antagonists)
NSAIDs (much less extent than opioids)
Antacids
Iron preparations
When to refer patients with constipation?
Sx persist longer than 2 Weeks
Fever
black tarry stools
marked abd pain/discomfort
Severe nausea/vomiting
Family history of IBD or colon cancer
Measures to help promote regular bowel habits
6-8 glasses of water a day
Add fiber to diet slowly (increase over 7-10 days)
Prunes
Moa of bulk laxatives
Forms emollient gels which retain water, swell and stimulate BM
Bulk laxative drugs
Psyllium- metamucil
Methylcellulose- citrucel (will not cause gas)
Calcium polycarbophil- fibercon
Advantage vs disadvantage of bulk laxatives
Advantage- Softens the stools better than docusate
Disadvantage- gas formation, impact on drug absorption
MOA of hyperosmotic agents
Draws fluid into colon due to hugh cone=centration of sugar.
Examples of Hyperosmotic drugs
MiraLAX, PEG
Adv vs Disadv of hyperosmotic agents
EXCELLENT FOR CHRONIC CONSTIPATION
disadv- 1-3 day onset
Dose of miralax
17 g po daily
