Pharmacology of Upper GI tract

?
  • Created by: Becca
  • Created on: 23-12-13 22:17
What is dyspepsia?
"Indegestion", dysfunction of the upper GI tract
1 of 14
What is GORD? What is it caused by?
Gastro-oesophageal reflux disease, leading to oesophagitis ("heart burn"). Caused by obesity/pregnancy -> fat/foetus push up gastric contents, increase intra-abdominal pressure & cause reflux -or- drugs cause relaxation of gastric sphincter
2 of 14
What are the two types of peptic ulceration?
Gastric & Duodenal
3 of 14
What is gastritis? What it caused by & what are the symptoms?
Gastritis = inflammation. Causes: NSAIDs, oral steroids (induced damage). Symptoms: epigastric pain, hunger pain relieved by eating (duodenal), night pain relieved by food/milk/antacids, vomiting, haematemesis, pain after eating, worse bending foward
4 of 14
What is the cause of gastritis? How do you test for it?
Helicobacter pylori: 90% duodenal ulcers, 70% gastric (infection -> chronic inflammation & gastritis -> ulceration). Test: urea breath test (carbon-13 urea), H. pylori contains urease which breaks down urea -> ammonia+CO2 -> C-13 detected exhaled CO2
5 of 14
What increases acid secretion?
Histamine via H2 receptors, gastrin, acetylcholine via M-receptors - M3 on parietal cells
6 of 14
What decreases acid secretion?
Prostaglandins (E2/I2), also cytoprotective via bicarbonate & mucous release
7 of 14
What are the 4 treatment options for gastritis?
Antacids, alginates, histamine H2 antagonists, proton pump inhibitors (PPIs)
8 of 14
How do antacids work?
Raise pH, rapid relief but not cure, sodium bicarbonate simplest, others include MgHCO3 ( cause diarrhoea) & AlHCO3 (cause constipation) -> use together
9 of 14
How do alginates & histamine H2 antagonists work?
Alginic acids form viscous foam, floats on gastric contents (raft), protects oesphagus during reflux. H2 antagonists: OTC low dose, short term relief, H2 receptors increase cAMP which activated proton pump, antagonists block receptors preventing this
10 of 14
How do proton pump inhibitors work?
Gold standard treatment, less side effects! Irreversible inhibition of proton pump (H+/K+ ATPase), activated by acidic pH (parietal cells), localised actions, increased risk of food poisoning
11 of 14
What is the treatment for H. pylori eradication?
Triple therapy (2 antibiotics + PPI and/or H2 antagonist) for 1 week then PPI alone
12 of 14
In the absence of H. pylori, which order should treatment be given?
Antacid/alginate + antacid -> H2 antagonist -> PPI
13 of 14
What is the ulcerogenic effects of NSAIDS (and oral steroids)? How do they work?
Associated with peptic damage/ulceration. Inhibit both isoforms (1+2) of COX preventing the production of prostaglandins which are protective, inhibit acid release, stimulate production of mucus & bicarbonate (neutralising) -> excess acid production
14 of 14

Other cards in this set

Card 2

Front

What is GORD? What is it caused by?

Back

Gastro-oesophageal reflux disease, leading to oesophagitis ("heart burn"). Caused by obesity/pregnancy -> fat/foetus push up gastric contents, increase intra-abdominal pressure & cause reflux -or- drugs cause relaxation of gastric sphincter

Card 3

Front

What are the two types of peptic ulceration?

Back

Preview of the front of card 3

Card 4

Front

What is gastritis? What it caused by & what are the symptoms?

Back

Preview of the front of card 4

Card 5

Front

What is the cause of gastritis? How do you test for it?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Medicine resources:

See all Medicine resources »See all Gastrointestinal System resources »