GI drugs

Question 1

diagnostic and therapeutic Indications for upper GI endoscopy?

Answer 1

Diagnostic:
Haematemesis/melaena
Dysphagia
Dyspepsia (greater than 55yrs old + alarm symptoms or
treatment refractory) Duodenal biopsy (?coeliac)
Persistent vomiting
Iron deficiency (cancer)

Therapeutic: Treatment of bleeding lesions
Variceal banding and sclerotherapy
Argon plasma coagulation for suspected vascular abnormality
Stent insertion, laser therapy
Stricture dilatation, polyp resection

Question 2

Diagnostic + therapeutic indications for colonoscopy?

Answer 2

Diagnostic: 
Rectal bleeding—when settled, if acute 
Iron-defi ciency anaemia (bleeding cancer) 
Persistent diarrhoea 
Positive faecal occult blood test 
Assessment or suspicion of IBD 
Colon cancer surveillance

therapeutic: 
Haemostasis (eg by clipping vessel)
Bleeding angiodysplasia lesion (argon beamer 
photocoagulation)
Colonic stent deployment (cancer)
Volvulus decompression (flexi sig)
Pseudo-obstruction
Polypectomy

Question 3

Dopamine receptor antagonist antiemetics?

Answer 3

Prochlorperazine
Metoclopramide (D2 antagonism and serotonin receptor antagonist)
domperidone
haloperidol

Question 4

Serotonin receptor antagonists antiemetics? (5-HT3 antagonists)

Answer 4

Ondansetron

Question 5

Anticholinergic antiemetic?

Answer 5

Scopolamine

Question 6

H1 receptor antagonists antiemetics?

Answer 6

cyclizine

cinnarizine

Question 7

Antiemetic of choice for reduced gastric motility cause of N+V?

Answer 7

Pro-kinetic agents
1st line - metoclopramide and domperidone

don’t use metoclopramide if pro-kinesis will negatively affect the GI tract eg. in complete bowel obstruction, gastrointestinal perforation, or immediately following gastric surgery

Question 8

Antiemetic of choice for chemically mediated cause of N+V? examples?

Answer 8

correct chemical disturbance if possible

ondansetron, haloperidol and levomepromazine

Secondary to hypercalcaemia, opioids, or chemotherapy

Question 9

Antiemetic of choice for visceral/serosal cause of N+V? examples?

Answer 9

Cyclizine and levomepromazine are first-line
Anti-cholinergics such as hyoscine can be useful

Due to constipation
Oral candidiasis

Question 10

Antiemetic of choice for raised ICP cause of N+V?

Answer 10

Cyclizine 1st line

also dexamethasone

Question 11

Antiemetic of choice for vestibular cause of N+V?

Answer 11

cyclizine

Refractory vestibular causes of nausea and vomiting can be treated alternatively with metoclopramide or prochlorperazine

Question 12

Antiemetic of choice for cortical cause of N+V? examples?

Answer 12

If anticipatory nausea is the clear cause, a short acting benzodiazepine such as lorazepam can be useful
Benzodiazepines are not ideal, BMJ best practice recommends use of cyclizine

May be due to anxiety, pain, fear and/or anticipatory nausea