Chapter 1 - Gastro-intestinal System Flashcards
Aminosalicylates are efficacious in the maintenance of remission of of which IBD?
Ulcerative colitis
What is the active component of aminosalicylates and where does it exert its therapeutic effect?
5- aminosalicylic acid (5-ASA)
Exerts it’s therapeutic effect in the lower bowel, which is why it is more efficacious in the maintenance of remission in UC than Chron’s disease
Which drugs are included in the aminosalicylate class?
Sulfasalazine, Mesalazine, Balsalazide. Olsalazine
What serious side-effect are aminosalicylates affiliated with?
Blood dyscrasias - patients should be advised to report any signs of unexplained bleeding, bruising, sore throat, malaise, fever, purpura during treatment
Irritable bowel syndrome (IBS) is categorised by….?
Recurrent episodes of abdominal pain + abnormal bowel motility (which can either be constipation, diarrhoea or both). Bloating and passage of mucus may also be presenting features.
Symptoms often relieved on defecation
What pharmacological treatments are available for the treatment of IBS?
Antispasmodics
Laxatives (if constipation if main presenting feature)
Anti-motility drugs e.g loperamide (if diarrhoea is main presenting feature)
Antimuscarinics (e.g hyoscine butylbromide)
Drugs which belong to antispasmodics class include:
Alverine
Mebeverine
Peppermint Oil
How do antispasmodics work?
Direct (local) effect on gut smooth muscle - causes relaxation. Does not generally have an effect on gut motility
Gastric and duodenal ulcers are generally associated with the use of which class of drugs or which microorganism?
NSAIDs
Helocobacter pylori
For H.pylori associated ulcers, what does initial therapy comprise of?
PPI
Clarithromycin
Amoxicillin or Metronidazole
If a patient has been recently treated with a macrolide what is the preferred treatment regimen for H.pylori eradication?
PPI + Amoxicillin + Metronidazole
If a patient has been recently treated with metronidazole, what is the preferred treatment regimen for H.pylori eradication?
PPI + Clarithyromycin + Amoxicillin
Treatment with PPI, Clarithyromycin, Amoxicillin and Metronidazole are all TWICE daily regimens, expect in the combination of which regimen?
Omeprazole 20mg BD \+ Amoxicillin 500mg TDS \+ Metronidazole 400mg TDS
The dose of clarithromycin if treating with amoxicillin for H.pylori induced gastric/duodenal ulcers is?
500mg BD
The dose of clarithromycin if treating with metronidazole for H.pylori induced gastric/duodenal ulcers is?
250mg BD
Dose of amoxicillin for the treatment of H.pylori induced gastric/duodenal ulcers is?
1g BD for all regimens apart from:
Omeprazole 20mg BD + Amoxicillin 500mg TDS + Metronidazole 400mg TDS
What is sucralfate?
mucosal protectant - forms an adherant complex with the mucosa of the ulcer site and provides a protective barrier over the ulcer
How should sucralfate be taken?
1 hour before food
Psychiatric reactions have been reported with regular use of H2-receptor antagonists (rantidine, cimetidine etc). Which groups of patients are more vulnerable to these side effects?
Elderly or the very ill
H2- receptor antagonists can be sold OTC for the short-term relief of which indication and for adults/children over ………. years old?
Short term relief of dyspesia (max 2 week supply)
licensed for >16 years old
What is misoprostol and what is it used for?
Synthetic prostaglandin analogue - protects the gastroduodenal mucosa by inhibiting basal, stimulated and nocturnal acid secretion.
Used for the healing and prophylaxis of NSAID induced ulcers.
Misoprotol is also a potent uterine stimulant - can be used to induce abortion
What should a female of child bearing age be aware of if taking misoprostol for the treatment of duodenal/gastric ulcers?
Effective contraception should be used. Misoprostol is teratogenic, particularly in the first trimester
When would you see PPIs being used intravenously?
Following endoscopic treatment of severe peptic ulcer bleeding, an intravenous, high-dose proton pump inhibitor reduces the risk of rebleeding and the need for surgery.
What is the MOA of PPIs?
Block the H+/K+ -ATPase pump of the gastric parietal cell, thereby reducing gastric acid secretion
