Gastrointestinal Disease Flashcards
What is dyspepsia?
Broad range of symptoms relating to dysfunction of upper GI tract incl. bloating, nausea, vomiting, epigastric pain, heartburn
State some drug causes of dyspepsia
- Calcium antagonists
- Nitrates
- Theophillines
- Bisphosphonates
- NSAIDs
- Corticosteroids
Acid is secreted from ____ cells by the ___ pump. It is stimulated by _____, _____ and _____.
Parietal; proton; histamine; acetylcholine; gastrin
What do alginate preparations do?
Increases stomach content viscosity (rafting agent), reducing reflux and protects oesophageal mucosa.
Combo of antacid and alginate.
How do H2 receptor antagonists work?
Inhibit H2 histamine receptors, inhibiting acid secretion
What are rare risks of proton pump inhibitors?
- Increases C.Diff risk
- ?Osteoporosis
How do PPIs reduce dyspepsia?
Block histamine to reduce acid production
How do NSAIDs lead to increased risk of gastric ulcer?
They block both good and bad (inflammatory) prostaglandins
What can helicobacter pylori (a gram negative bacteria) cause?
Gastritis and ulcers (chronic)
How is gastro-oesophageal reflux disease (GORD) treated in adults?
PPI for 1-2 months.
?PRN use, dose depends on sx.
How does infant and child GORD treatment differ?
Infant = Alginate 1-2 week trial Child = 1 month trial H2 antagonist or PPI
What neurological site is known as the vomit centre?
Chemoreceptor trigger zone (CTZ)
Which NTs are involved in vomiting?
Aceytycholine, histamine, 5-HT, Dopamine
For what types of nausea are H1 receptor antagonosts effective?
- Motion sickness
- Post-op nausea/vomiting (PONV)
- Pregnancy
When are Ach muscarinic-receptor antagonists indicated?
Motion sickness
Phenothiazines antagonise ____ receptors in the _____. They are effective for reducing _____.
Dopamine; CTZ; PONV
What routes are prochlorperazine administered?
IM, buccal, rectal
What routes are levomepromazine administered?
IM, SC
When are metoclopramide and demperidone used? What do they do?
Cancer chemotherapy.
DA-receptor antagonists. Act on CTZ to increase stomach/gut motility
Ondansetron and granisetron have what mechanism of action?
5-HT3 antagonists
State common causes of constipation
Immobility, inadequate diet, inadequate fibre, drugs (e.g. opiates, disease)
What are the 4 classes of laxatives?
- Bulkers (increase faecal mass & peristalsis)
- Osmotic & faecal softeners
- Stimulant
