Methylcellulose, MOA, Increased bacterial mass causes distension in colon, Activated stretch receptors stimulate peristalsis, Decreased transit time, Use, Acute or chronic constipation (better for chronic), Effect w/in 12-24 hrs, Not for prompt bowel evaculation, SE, Flatulence and bloating d/t bacteria, Not as bad with methycellulose
Saline laxatives, Magnesium citrate, Use, Constipation, Bowel prep, Onset = .5-6 hrs, SE, Hypermagnesemia, Sodium phosphate, Enema works very quickly (2-15 minutes), Oral, Use, Bowel prep, SE, MUST drink at least 64 oz water to prevent acute phosphate neuropathy, PO3 binds Ca++ & and precipitates in DCT, Hypovolemia causs massive salt/water resorb, CI in kidney problems, CHF, ACEi
Non-digestible sugars & alcohols, Lactulose, Use, Acute or chronic constipation, Onset: 24-48 hrs, SE, Flatulence and cramps
Polyethylene glycol (PEG), Use, Constipation (A&C), Onset = 1-3 days, Bowel prep, Onset = 1-2 hrs, *Add electrolytes to prevent imbalance*
MOA, Create osmotic gradient that increases intra-luminal volume and pressure in small intestine and/or colon
Bisacodyl, MOA, Acts as irritant, Stimulates enteric NS, Peristalsis, Increase H2O and electrolytes in lumen, Peristalsis, Use, A&C constipation, Onset = 8-10 hrs (overnight laxative), Bowel prep: Used in combo w/ PEG
Docusate sodium, MOA, Anionic surfactants allow water and lipid penetration into stool, Use, Don't help w/ constipation!, Don't make you go, only help you go, Post surgery if given opiod
MOA, Selective type 2 Cl channel activator, Increases intestinal fluid secretion and motility
Use, Chronic constipation, Constipation predominant IBS
SE, Nausea, diarrhea, Cost
Opioids, Diphenoxylate + Atropine, LD atropine prevents drug abuse (get cholernergic Sx if dose too high), Loperamide, These two have the greatest ratio of intestinal to CNS activity!
MOA, Antagonist Mu and delta receptors in enteric neurons/muscle, Reduced peristalsis and intestinal secretions
Use, Control diarrhea d/t almost any cause
Bismuth Subsalicylate, MOA, Bismuth: binds enterotoxins to prevent traveler's diarrhea, Salicylate: Inhibits production of PGs to deacreas intestinal secretions, Not as good as Loperamide!
Tx has high placebo effect!
Constipation - OTC laxatives
Diarrhea - Loperamide
Pain - Anticholinergics/antidepressants
Lubiprostone, affects serotonin receptors, Big gun!!!
Cholestyramine reduces bile and colonic secretion