GI Pharmacology Flashcards
What are some of the symptoms of GORD?
- Painful heart burn
- Cough
- Larygntitis
- Astha
- Dental erosion
What are some of the complications of GORD?
- Oesophagitis
- Ulceration
- Haemorrhage (anaemia)
- Stricure formation
- Barret’s oesophagus
What medications can exacerbate the symptoms of GORD?
Anything that relaxes smooth muscle
- alpha bockers
- anticholinergics
- benzodiazepines
- beta blockers
- CCBs
- NSAIDs
- Nitrates
- Theophylline
- TCAs
What are some risk factors for developing GORD?
- Older age
- Hiatus hernia (lower oesophageal sphinter into thorax)
- Obesity
- Pregnancy
- Smoking
- Alcohol consumption
What lifestyle changes would you recommend for someone experiencing GORD symptoms?
- Weight loss
- Avoid trigger food
- Eat smaller meals
- Eat earlier in the day
- Reduce alcohol/ caggeine intake
- Stop smoking (limited evidence)
What are the pharmacological steps for treating GORD?
- Introduce proton pump inhibitor first line
- If unsuccessful- add in H2 Receptor Antagonist
Name 2 proton pump inhibitors
- Omeprazole
- Lansoprazole
What is gastritis?
An inflammatory change in the gastric mucosa
Can be erosive/ non-erosive. Acute / chronic
What are some of the symptoms of gastritis?
- Burning epigastric pain
- Food may increase or decrease pain
- Nausea
- Vomiting
What are some of the risk factors for developing gastritis?
- H. pylori infection
- Chronic NSAID use
- Bile reflux
- Chronic alcohol use
How do you manage erosive gastritis?
- Remove irritant (NSAID, alcohol, bile)
- Add PPI or H2 Receptor antagonist
How do you eradicate H. pylori?
Triple therapy
- PPI
- Amoxicillin
- Clarithromycin or Metronidazole (effectove but has side effects)
How do PPIs work?

How do H2 receptor antagonists work?

Name a H2 receptor antagonist
Ranitidine
What is peptic ulcer disease?
A defect in the gastric or dueodenal mucosa that exptends through the muscularis mucosa
What are some the symptoms of peptic ulcer disease?
- Epigastric pain after meals
- soon after meals (gastric ulcer)
- 2-3 hours after (duodenal)
What are some of the risk factors for developing peptic ulcer disease?
- H pylori infection
- NSAIDs
How do manage peptic ulcer disease that is H.pylori negative?
-
Stop NSAIDs
- consider switching to COX-2 selective NSAID e.g. celecoxib
- doesn’t effect COX-1 prostaglandin synthesis which is protective for the GI tract
- Add PPI (+ H2 RA if unresponsive)
How do you test for H.pylori?
- Carbon 13 urea breath test
- Or stool antigen test

What are the 2 different isoforms of COX enzymes and where are they distributed throughout the body?
COX-1
- high concentration in platelets, vascular endothelial cells, stomach and kidney
- produces prostaglandings necessary to maintain endocrine, renal function, gastric mucosa integrity and haemostasis
COX-2
- normal conditions, very low levels
- rapdily increases at time of tissue damage

What are the benefits and disadvantages of COX-2 inhibitors
Benefit:
- Gastric protection
Disadvantage:
- not good for CVS if given long term
- High levels of TXA2 → pro-thrombotic
What factors of the stomach offer protection against mucosal injury?
- Acid - innate defence against bacterial invasion
- Mucus - lubricates, traps bacteria, barrier against pepsin (protease that can auto-digest stomach)
- Epthelial replaced 2-4 days
- Good mucosal blood flow- if epithelium damaged rapid repair can occur
What are the two types of gastric prostalandins and what are their effects?
PGE2 & PGI2
- Potent vasodilators
- Decrease acid secretion (at high levels)
- Stimulate mucus and bicarb secretion in stomach
- Reduce permeability of epithelium to backflow of acid
- Reduce release of inflammatory mediators
- Promote ulcer healing


