ILA 3 - PK AND PD IN THE REAL WORLD OF CLINICAL PRACTICE

Question 1

In order to induce anaesthesia quickly, what characteristics should the drug have in terms of its protein binding and lipid solubility?

Answer 1

low protein
high lipid solubility

Question 2

Explain in terms of the drug distribution of the IV drug why an additional volatile drug needs to be given as soon as the patient is asleep
What would happen if it were not given?

Question 3

Define and explain the terms:
a. agonist and antagonist in relation to drug action - give an example of each
b. competitive and non-competitive antagonists - give an example of each

Question 4

In addition to ‘receptors’, what 3 other drug targets are there?
For each target give an example of a drug that acts on it and how it produces its desired effect

Answer 4

1. enzymes
2. transporters/carrier proteins
3. ion channels

Question 5

Explain this difference in terms of Morphine’s bioavailability and first pass metabolism (define both terms)

Question 6

Roughly how much more oral morphine is required compared to IM morphine?

Question 7

In terms of morphine’s metabolism and metabolites, explain why this is (prescription of a lower dose)

Answer 7

• morphine metabolised in the liver to morphine 6 glucuronide (more potent than morphine)
• excreted by kidneys, so not readily secreted if patient has renal failure
• this requires dose and frequency of administration of morphine to be reduced

Question 8

You are the head of drug development at a major pharmaceutical firm. Describe the properties you would want from the ideal IV anaesthetic induction drug