Drugs and the gut Flashcards
What does 5ASA stand for?
5 aminosalicylic acid
Examples of 5ASA and their sites
Sulphasalazine (colon)
Mesalazine (small bowel and colon)
Olsalazine (colon)
Balsalazide (colon)
Site of release when 5ASA is given orally
Depends on formulation (coating and azo bond)
Indication for 5ASA
Mild/moderate UC
Colonic Crohns
Maintenance UC = prevents recurrence of inflammation and possibly colorectal cancer
MOA of 5ASA
Unknown
Poorly absorbed
Reactive oxygen species scavengers
Modulates prostaglandin and leukotriene synthesis from arachidonic acid
Modulates cytokine profile
PPARgamma agonist (peroxisome proliferator activated receptor gamma)
5ASA route
Proctitis = suppository
Left sided = enema
Pan = oral
5ASA side effects
Rare nephrotoxicity rash worsening of colitis pancreatitis percarditis
Examples of corticosteroids
Hydrocortisone
Prednisolone
Budesonide
Classes of corticosteroids
Glucocorticoid
Low mineralocorticoid
Budesonide uses
topical
first pass metabolism
fewer systemic side effects
Indication for corticosteroids
induction of remission
never for maintenance
MOA of corticosteroids
Immunosuppressive Glucocorticoid receptors Regulates transcription of 100s of genes Reduces IL1, TNFa, IL8 Reduces NO Prevent leucocyte migration
Routes of administration for corticosteroids
According to site and severity of IBD
- oral
- IV
- enema
- suppository
SE of corticosteroids
- HTN
- DM
- central obesity
- osteoporosis, myopathy
- acne, bruising
- cataracts
- depression, psychosis, euphoria, insomnia
- pituitary/adrenal suppression
- GF (children)
- sepsis in Crohns, candida
Duodenal peptic ulcer disease cause
H pylori
Gastric peptic ulcer disease cause
H pylori
NSAIDs & steroids
Tx for peptic ulcer disease
H pylori eradication
Anti secretion therapy
Examples of drugs for anti-secretion therapy
Omeprazole lansoprazole pantoprazole rabeprozole esomeprazole ranitidine
Class of drugs for anti-secretory therapy
PPIs
MOA of PPIs
histamine receptor 2 antagonists
Indications for ant-secretory therapy
PUD
GORD
Prevention of ulcers in patients on NSAIDs
Zollinger-Ellison syndrome
Routes of administration for anti-secretion therapy
Oral
IV
Side effects of anti secretion therapy
Diarrhoea
Headache
Increased risk of C. difficile
Weak inhibitors of cytochrome P450 (so need to be careful with some drugs)
Which drugs do you need to be careful of with anti-secretory therapy
Phenytoin
Warfarin
Theophylline
(as anti-secretaries are weak inhibitors of cytochrome P450)