peptic ulceration and altered bowel habits Flashcards
antacids
made of alkaline salts
neutralise stomach acid
bind to and inactivate pepsin
adverse effects:
constipation
diarrhoea
pepsin
protein digesting enzyme
H2-receptor antagonist
cimetidine, ranitidine
competitively block the action of histamine on the parietal cell
avoid cimetidine in patients on warfarin, phenytoin, theophyline
PPIs
omeprazole, lansoprazole
irreversible inhibition of H+/K+ ATPase responsible for secretion from parietal cells
interactions with clopidogrel
H. pylori eradication
triple therapy:
PPI, amoxicillin, clarithromycin/metronidazole
quad therapy:
omeprazole, 2 ABx (tetracycline and metronidazole) and bismuth chelate
bulk forming laxatives
increase volume of non-absorbable material in the gut
distend the colon and stimulate peristalsis
take with plenty of fluid and may take a few days to act
C/I: dysphagia, obstruction, colonic atony, faecal impaction
eg: bran powder, fybogel
osmotic laxatives
increase water content in the bowel vis osmosis
distend the colon and stimulate peristalsis
C/I: intestinal obstruction
eg: lactulose, macrogol (movicol)
stimulant laxatives
increae peristalsis
increase water and electrolyte secretion by the mucosa
C/I: obstruction, acute colitis
eg: senna
faecal softeners
promote defecation by softening or lubricating the stool
particularly useful for fissures
C/I: not for children under 3yo
eg: arachis oil, liquid paraffin (but not for a prolonged period - anal seepage, lipoid pneumonia)