Pharmacogenetics

Question 1

Why do some individuals respond differently to drugs

Answer 1

They show Single Nucleotide polymorphism which is mutations which lead to amino acid substitutions

Question 2

What is the impact of polymorphisms of Cytochrome P450 CYP2D6

Answer 2

Can be slow metabolisers or drugs or fast metabolisers of drugs

Question 3

How is codeine affected by metabolism

Answer 3

Codeine is turned into morphine for pain relief but If the person is a slow metaboliser, then the drug won’t be of use

Question 4

What is the dose of warfarin determined by and why

Answer 4

The individual patient

-Because there is CYP2C9 polymorphism so some people may be more sensitive/insensitive it to it than others

Question 5

If you have differences in Vitamin K epoxide reductase complex 1, what may this mean

Answer 5

You may have warfarin resistance so you may need a higher dose of warfarin

Question 6

When do you measure the InR when using warfarin

Answer 6

On day 3

Question 7

What do you do if the INR is high on the third day of using warfarin

Answer 7

Use a lower maintenance dose of warfarin

Question 8

What do you do if the INR is low on the third day of using warfarin

Answer 8

Use a higher maintanence dose

Question 9

Do all patients benefit from aspirin

Answer 9

No

-25% of people are aspirin resistant