Inhibition

Question 1

4 forms of inhibition

Answer 1

Competitive
Non-competitive
Uncompetitive
Irreversible (suicide)

Question 2

3 types of competitive inhibition and examples

Answer 2

Non substrate (quinidine for 2D6)
Other substrate (diazepam for 2C19)
Mixed (reacts with Fe in haem group)

Question 3

What is ketaconozole inhibition

Answer 3

Mixed competitive
Replaces with triazoles - more anti fungal activity, less inhibition

Question 4

Mechanism of non-competitive and example

Answer 4

Allosteric site binding
St John’s wort on 2D6 in vitro

Question 5

Mechanism of uncompetitive

Answer 5

Rare
Binds ES complex
Increase affinity of binding but inhibitor makes nonfunctional

Question 6

Mechanism of irreversible and example

Answer 6

Bind active site for long time
Can change shape of active site
Grapefruit juice on 3A4

Question 7

Use of inhibitor for alcoholism

Answer 7

Disulphiram

Question 8

Clinical consequence of inhibitor

Answer 8

Grapefruit juice causes build up of terfenadine
- cardiac arrhythmias