Constipation & Diarrhea Flashcards
What’s the tx duration for constipation, as per FDA?
OTC laxatives should be limited to 7 days unless under medical supervision
What’s constipation?
Infrequent or hard stools or difficulty passing stools
No bowel movements after more than 3 days
What’s the recommended first-line tx for constipation?
Bulk-forming laxatives that contain either;
Psyllium
Methylcellulose or
Polycarbophil
What’s another commonly used laxative?
Stool softener (Docusate)
What’s the stool softener (Docusate) especially helpful for?
Iron-induced constipation
Bcuz iron causes compact, hard stools which are difficult to pass
List medical conditions where constipation is common
Cerebrovascular events
Parkinson dx
Spinal cord tumors
Diabetes
Hypothyroidism
Multiple sclerosis
Irritable bowel syndrome (constipation-predominant)
Anal disorders (anal fissures, fistulae, rectal prolapse)
List main meds that are constipating
Opioids
Anticholinergic drugs
Verapamil
Iron (use Docusate to avoid hard, compact stools)
List other meds that are constipating
Antihistamines, phenothiazines, tricyclic antidepressants, antispasmodics, urge incontinence drugs, esp darifenacin (Enablex)
Non-DHP CCBs
Clonidine
Bismuth
Aluminum antacids (Mg often in combo with Al to counter this effect)
Tramadol, tapentadol
Colesevelam
Milnacipran
Ranolazine
Varenicline
5-HT3 receptor antagonist e.g. Ondansetron
Phentermine/topiramate
Aripiprazole
What drugs are the worst offenders of constipation?
Opioids
Whats usually scheduled with an opioid?
A stimulant laxative (usually senna) is given first with or without stool softener (docusate)
What factors should a pharmacist dispensing opioids consider?
Dose
Frequency
Pt at baseline
What’s used if the pt is constipated now and req tx?
Options are different from those used to prevent
Lactulose
Sorbitol
Milk of magnesia (MOM)
Magnesium citrate
Polyethylene glycol
What’s does a successful colonoscopy entails?
Requires a complete and thorough bowel prep
Issues with sodium phosphate?
Sodium phosphate can cause:
Fluid and electrolyte abnormalities (particularly risky in pts with renal or cardiac dx)
Why do some bowel prep agents req MedGuide?
Because of fluid and electrolyte abnormalities
What types of pts should extra caution be used in wrt concurrent use of bowel prep agents?
Pts with cardiovascular dx
Renal insufficiency
Pts on diuretics (loops, due to additional fluid loss)
NSAIDs
What’s ok to consume prior to bowel prep?
“Clear liquid diet” ONLY
E.g. Water, clear beef/chicken broth, fat-free consommé, juices (Apple, prune, grape, cranberry and cider), coffee or tea (without milk or cream), clear gelatin (without fruit pieces), Popsicles (without fruit pieces or cream) fruit ices (no fruit pieces)
List bulk-producing laxatives
Psyllium (Metamucil, others)
Calcium polycarbophil (FiberCon, others)
Methylcellulose (Citrucel)
What’s the brand name of Psyllium (bulk-producing laxatives)?
Metamucil
What’s the brand name of Calcium polycarbophil (bulk-producing laxatives)?
FiberCon
What’s the brand name of Methylcellulose (bulk-producing laxatives)?
Citrucel
What’s the first-line tx of constipation and drug of choice in pregnancy?
Bulk-producing laxatives:
Psyllium (Metamucil, others)
Calcium polycarbophil (FiberCon, others)
Methylcellulose (Citrucel)
How should bulk-producing laxatives (Psyllium (Metamucil); Calcium polycarbophil (FiberCon); Methylcellulose (Citrucel)) be used with other drugs?
2 hrs before/after drugs
List agents under emollients, lubricants (stool softeners)?
Docusate Sodium (Colace)
What’s the brand name of Docusate sodium (emollients, lubricants, stool softeners)?
Colace
What’s the caution when recommending agents?
Take caution when recommending pdts by brand name, as many brand names can refer to multiple pdts
List agents under stimulants and irritants
Senna (Ex-Lax)
Bisacodyl (Dulcolax)
Whats the brand name of Senna (agents under stimulants and irritants)?
Ex-Lax
Whats the brand name of Bisacodyl (agents under stimulants and irritants)?
Dulcolax
When is SE of senna increased?
When high doses are used
What’s the caution in recommending brand name of senna?
Same brand names can refer to multiple pdts
List rx agents for constipation
Lubiprostone (Amitiza)
Linaclotide (Linzess)
What’s the brand name of Lubiprostone (rx agents for constipation)?
Amitiza
Whats the main SE of Lubiprostone (Amitiza)?
Nausea
What’s the black box warning associated with Linaclotide (Linzess)?
Don’t use in pts < 18 yrs
What’s the SE of Linaclotide (Linzess)?
Diarrhea
Which rx agents should be dispensed with a MedGuide?
Linaclotide (Linzess)?
MOA of stimulants/irritants?
They work by reducing water and electrolyte absorption by stimulating colonic neurons and irritating the mucosal lining of the colon
MOA of Osmotic laxatives?
Cause fluid to be retained in the bowel lumen, with a net increase of fluid secretions in the small intestines
List acute (stat) tx and bowel preps
Bisacodyl rectal
Osmotics (mg salts eg MOM; lactulose; sorbitol)
Sodium phosphates (Fleet enema, OsmoPrep)
Nonabsorbable soln (PEG)
List osmotic agents used in constipation
Magnesium salts (MOM)
Lactulose
Sorbitol
What’s warning ass with sodium phosphates (Fleets enema, OsmoPrep)?
Don’t use sodium phosphates in CHF, renal dx, low Calcium or high PO4
List Nonabsorbable solutions; also used for bowel prep
Polyethylene glycol (Golytely, MiraLax, Carbowax)
What should be avoided for bowel prep?
Red or blue/purple drinks
List agents used in opioid-induced constipation tx
Methylnaltrexone (Relistor)
Alvimopan (Entereg)
What’s the brand name of Alvimopan (opioid-induced constipation tx)?
Entereg
When is Methylnaltrexone (Relistor) used?
Only in pts on opioid who have failed DSS + laxative (senna, bisacodyl)
How should Methylnaltrexone (Relistor) be used?
Don’t use routinely
What’s the black box warning of Alvimopan (Entereg)?
REMS drug
Short-term hospital use only (max 7 days - no more than 15 doses)
What’s the CI of Alvimopan (Entereg)?
Pts who have taken therapeutic doses of opioids for more than 7 consecutive days prior to use
What’s diarrhea?
Diarrhea occurs when there is an increase in the number of bowel movements or bowel movements are more watery and loose than normal
List main meds that can cause diarrhea
Antacids containing magnesium
Antibiotics esp. broad spectrum ABs and Clindamycin, Erythromycin
List other meds that can cause diarrhea
Colchicine
Laxatives
Metoclopramide
Misoprostol
Quinidine
Etc
What’s the cause of most cases of diarrhea?
Most cases are viral
Whats the most common bacterial cause of diarrhea?
E.coli
MOA of bismuth subsalicylate in diarrhea?
Exhibits both antisecretory and Antimicrobial effects when used as an antidiarrheal
List antidiartheals agents
Bismuth subsalicylate (Pepto-Bismuth, others)
Loperamide (Imodium, Anti-Diarrheal, Diamode, others)
Diphenoxylate 2.5mg + Atropine 0.025mg (Lomotil)
What’s the brand name of Bismuth subsalicylate (antidiartheals agents)?
Pepto-Bismol
What’s the brand name of Loperamide (antidiartheals agents)?
Imodium
Anti-diarrheal
Diamode
What’s the brand name of Diphenoxylate 2.5mg + Atropine 0.025mg (antidiartheals agents)?
Lomotil
Which antidiartheals is a C V?
Diphenoxylate 2.5mg + Atropine 0.025mg (Lomotil)
SE of bismuth subsalicylate (Pepto-bismol)?
Black tongue/stool
What’s the counseling note for loperamide (Imodium, Anti-Dirrheal, Diamode)?
Don’t self-treat for > 2 days
What should diarrhea tx include?
Fluid and electrolytes
Imp for all, but esp in children
When’s Imodium and Lomotil not recommended?
C. Difficle infections
What may be done b4 starting antidiartheals?
Rule out lactose intolerance as a cause of the diarrhea by stopping use of diary pdts
