Lecture 4

Question 1

Define local anaesthetic action

Answer 1

Reversible binding to and inactivation of sodium ion channels

Question 2

What should anaesthetics have?

Answer 2

fast onset and recovery
few side effects/high therapeutic index
aqueous solubility and for easy formulation

Question 3

What is the role of general anaesthetics?

Answer 3

Sedative-hypnotics act by enhancing the inhibitory actions of GABAA receptors

Question 4

Why is having a nitrogen at physiological pH important?

Answer 4

Forms a salt so you have a good chance of increasing the aqueous solubility e.g. amines in the side chain

Question 5

What happens to esters at the end of the chain?

Answer 5

Much more open and available to the environment and therefore much more likely to be rapidly metabolised

Question 6

Why are benzodiazepines less used as anaesthetics?

Answer 6

Due to cardiovascular depression and prolonged recovery times