GI Drugs

Question 1

Tx a “severe” flare of UC?

Answer 1

(>6 bowel movements and systemically unwell)

IV hydrocortisone and fast fluids

Question 2

Tx a “mild” flare of UC?

Answer 2

oral prednisolone 30mg given over 24 hours

Question 3

what types of laxatives are there?

Answer 3

“BOSS”

• bulk forming
• osmotic
• stimulant
• stool softening

Question 4

examples of bulk forming laxatives?

Answer 4

methylcellulose
ispaghula husk
sterculia

Question 5

downsides of bulk forming laxatives?

Answer 5

• slow to work
• adequate fluid intake should be maintained to avoid intestinal obstruction
• not used in atony or faecal impaction

Question 6

examples of osmotic laxatives?

Answer 6

lactulose
macrogol
Mg-hydroxide/sulfate
phosphate enema

Question 7

which laxative is used for hepatic encephalopathy?

Answer 7

lactulose

Question 8

how do osmotic laxatives work?

Answer 8

↑ water in the small bowel

Question 9

CI for osmotic laxatives?

Answer 9

bloating
obstruction or risk of perforation
(don’t use phosphate enema in acute abdo!)

Question 10

CIs for stimulant laxatives?

Answer 10

intestinal obstruction
cramping
(atony)
(undiagnosed acute abdo!)

Question 11

examples of stimulant laxatives?

Answer 11

senna
sodium picosulfate
bisacodyl
glycerol

Question 12

examples of stool softeners?

Answer 12

docusate sodium
arachis oil (rectal)

Question 13

CIs for stool softeners?

Answer 13

already soft stool! but good for faecal impaction

Question 14

Tx acute GI bleed?

“8 Cs”

Answer 14

- ABC, O2, protect airway (NBM)
C - 2 x large bore cannula (14-16G)
C - cross-match 6 units
C - crystalloid IV fluids <1 litre
- if shocked, give blood, otherwise only if Hb<7
C - correct abnormal clotting (vit k, FFP, plts)
C - catheter (fluid output)
C - call surgeons
C - camera (urgent endoscopy)
C - stop culprit drugs

(risk of varices - alcohol/liver? terlipressin IV 1-2mg + IV Abx)

Question 15

Tx flare of Crohn’s?

Answer 15

mild flare with prednisolone 30 mg daily orally

severe flare with hydrocortisone 100 mg 6-hourly IV and IV fluid, nil by mouth and antibiotics

if the patient has rectal disease, use rectal hydrocortisone too

Question 16

Tx for maintaining remission in Crohn’s?

Answer 16

azathioprine/6-mercaptopurine (pro-drug, metabolized by the liver to 6-mercaptopurine)

10% of the population have abnormal accumulation of 6-mercaptopurine , ↑ risk of liver and BM toxicity

check TPMT (enzyme) levels before starting either drug

If TPMT is found to be ↓, consider starting methotrexate instead

Question 17

Tx chronic D (that has proven to be non-infectious)?

Answer 17

loperamide

codeine

Question 18

usual dosage of omeprazole for GORD?

Answer 18

10 mg orally daily

increasing to 20 mg orally daily if Sx return

Question 19

can you use PPI to Tx GI S/E of alendronic acid?

Answer 19

bisphosphonates are direct irritants to the upper GI tract

Sx not improved by PPIs

Question 20

Tx C Diff?

Answer 20

first episode - oral metronidazole 10–14 days
second or subsequent episode - oral vancomycin 10-14d
life-threatening infection, or in patients with ileus - oral vancomycin + i/v metronidazole