Pharmacology

Question 1

Name 3 agonists of H+k+ ATPase

Answer 1

Gastrin, acetylcholine, histamine

Question 2

Name 3 antagonists of H+k+ ATPase

Answer 2

Prostaglandins, somatostatin, gastrin inhibitory peptide

Question 3

What actives PPIs

Answer 3

Acid (coated to prevent premature activation)

Question 4

Where are PPIs absorbed

Answer 4

Small intestine

Question 6

Where are PPIs activated?

Answer 6

Parietal cell

Question 7

What is the bond that PPIs bond to H+K+ ATPase?

Answer 7

Covalently (irreversibly)

Question 8

where is HCL made

Answer 8

parietal cells

Question 9

How is a proton pump used in HCL porduction

Answer 9

ATP is used to exchange a hydrogen ions for potassium ions

Question 10

What does H+ combine with in the gastric lumen

Answer 10

CL- to form HLC

Question 11

what id expressed on the parietal cell in responce to a meal

Answer 11

H+K+ATPase

Question 12

are all the ATPase pumps expressed on parietal cells?

Answer 12

NO spells no

Question 13

with a single PPI does what fraction of pumps are inhibited?

Answer 13

2/3

Question 14

What is the PPI half life?

Answer 14

1-2 hours

Question 15

what happens to pumps by the meal following PPI consuption?

Answer 15

remaining pumps activated and acid production continues at an attenuated level.

Question 16

how long before meal should you take PPI?

Answer 16

30 mins

Question 17

Example of PPI?

Answer 17

lansoperazole

Question 18

is chronic use good?

Answer 18

no, it has been linked to side effects

Question 19

what are the main effect of prostoglandins in stomach?

Answer 19

• antagonsit of gastric acid
• ## cause musus secretion

Question 20

what inhibits prostoglands?

Answer 20

NSAIDS

Question 21

What are the substances that PPIS may inhibit the absorption of?

Answer 21

• calcium (increased risk of bone fracture but need an acidic enviroment)
• magnesium ( linked to chronic kidney diesease, increased pH negativly affects transporters)
• Vitamin B12 ( conginitve funciton, released via gastric acid and pesin)

Question 22

What are the two mechaisms of PPIS that may cause dementia?

Answer 22

• Vitmain B12 defficiency
• PPI reduce breakdown of B-amyloid

Question 23

Does PPI use increase or decrease risk of C-diff?

Answer 23

increase because less gastric acid increases the risk of bacterial colonistion

Question 24

3 examples of conservative managment for acid reflux

Answer 24

1Weight loss
2Elimination of dietary triggers
3Avoidance of alcohol and tobacco
Avoid tight fitting clothing
Elevation of the head at night
Chewing gum / lozenges to salivation

Question 25

example of H2 antagonist?

Answer 25

famotidine

Question 26

what is an alternative pharmacologic therapy to PPI?

Answer 26

Histamine receptor 2 antagonist

Question 27

what is H2 blocker mechanism of action?

Answer 27

competivie antagonist, (compete with histamine)

Question 28

What mediated CAMP?

Answer 28

Histamine

Question 29

why are PPIs more effective than H2RA?

Answer 29

H2RA only inhibit one elment of the pathway for gastric acid secretion - other agonists still at work

Question 30

name a anaesthetic

Answer 30

Lidocain

Question 31

what is lodocain used in?

Answer 31

throat spray and instilla gel

Question 32

c

Question 33

Name 4 tests for H-pylori?

Answer 33

-blood test -stool antigen test -clo test -C13 urea breath test

Question 34

What may cause a false negative for H-pylori?

Answer 34

-antibiotics - PPIs within two weeks

Question 35

What is H-pylori treatment?

Answer 35

-tripple regime (PPI with two antibiotics

Question 36

Why are PPIs needed to treat H-pylori?

Answer 36

They reduce the acid environment so that H-pylori shifts to a replicating phenotype (antibiotics are ineffective against non replicating)

Question 37

What is the moa of lidocaine?

Answer 37

-blocks voltage gated sodium channels on the nerve cell membranes - nocioceptors

Question 38

What drugs shouldn't you have with lidocaine?

Answer 38

Cocaine and nitrous oxide and benzocain

Question 39

What drugs may be used to treat hypercontractility?

Answer 39

Nitrates + calcium channel blockers

Question 40

What is the moa of nitrates?

Answer 40

nitrates increase the release of nitric oxide in smooth muscle which causes sm relaxation

Question 41

what is the impact of an influx of calcium in smooth muscle?

Answer 41

Muscle contraction

Question 42

example of a nitrate?

Answer 42

isosorbide dinitrate

Question 43

example of a calcium channel blocker?

Answer 43

nifedipine

Question 44

calcium channel inhibitors mechanism of action

Answer 44

calcium channel inhibitors block the influx of calcium so muscle contractility is attenuated

Question 45

What drugs may improve gatro-paresis + gastric emptying?

Answer 45

prokinetics

Question 46

what does dopamine do?

Answer 46

Dopamine inhibits the release of acetylcholine. decrease motility in the stomach and proximal small bowel.

Question 47

what drug would block dopamine?

Answer 47

D2 receptor antagonists

Question 48

example of prokenetic

Answer 48

metoclopramide (crossed blood brain barrier and blocks actions of dopamine )

Question 49

Domperidone side effects

Answer 49

does not cross blood brain barrier but association between this and the risk of sudden cardiac death, ventricular tachyarrhythmias

Question 50

Name 4 causes of constipation

Answer 50

- drugs (opiods, antimuscarins, calcium channel blockers, organis (diabetes, hypercalcaemia, hypokalaemia, hishsprungs structural ( anal or colonic strictures) dyssynergia, IBS

Question 51

3 steps of laxatives

Answer 51

1. bulk 2. osmotic 3. stimulant

Question 52

what type of laxative is lactulose

Answer 52

osmotic

Question 53

what type of laxative is fybogel?

Answer 53

bulk

Question 54

name a stimulent laxative

Answer 54

senna

Question 55

osmotic

Answer 55

Osmotic action draws fluid into bowel, distends wall, stimulates mechanoreceptors, increases peristalsis via neuronal reflex.

Question 56

Bulk

Answer 56

High in fibre / non-digestive sugars, retain water in gut, increased bulk increases peristalsis

Question 57

Stimulant

Answer 57

increase peristalsis via irritation

Question 58

Emollient, softeners

Answer 58

Stim. salt and water secretion, lubricates gut wall, detergent effect on colonic material – stool softer and easier to pass

Question 59

name a Selective serotonin type 4 receptor (5-HT4) agonist

Answer 59

prucalopride

Question 60

what happens when a seratonin agonist is bound?

Answer 60

- increases cAMP causing an increase in acetylcholine release

Question 61

name treatment for diarhoeah

Answer 61

loperamide (stimulates absorption of water and electrolytes in GIT)

Question 62

What drugs may treat hypomotility?

Answer 62

Prokentoic (dopamine antagonist)

Question 63

What should be tried if all laxatives don't work?

Answer 63

Prucalpride DONT USE FOR OPOIDs