P450 inhibitors/inducers

Question 1

Effect of P450 inducer on INR in warfarin takers

Answer 1

INR will decrease

Question 2

Effect of P450 inhibitors on INR in warfarin takers

Answer 2

INR will increase

Question 3

What effect do antiepileptics (phenytoin, carbamazepine) have on P450 system?

Answer 3

P450 inducers

Question 4

What effect do barbiturates (phenobarbitone) have on P450 system?

Answer 4

P450 inducers

Question 5

What effect does rifampicin have on P450 system?

Answer 5

P450 inducer

Question 6

What effect does St John’s wort have on P450 system?

Answer 6

P450 inducer

Question 7

What effect does chronic alcohol intake have on P450 system?

Answer 7

P450 inducer

Question 8

What effect does griseofulvin have on P450 system?

Answer 8

P450 inducer

Question 9

What effect does smoking have on P450 system?

Answer 9

P450 inducer - affects CYP1A2, therefore smokers require more aminophylline

Question 10

What effect do antibiotics (ciprofloxacin, clarithromycin/erythromycin) have on P450 system?

Answer 10

P450 inhibitor

Question 11

What effect does isoniazid have on P450 system?

Answer 11

P450 inhibitor

Question 12

What effect do cimetidine, omeprazole have on P450 system?

Answer 12

P450 inhibitor

Question 13

What effect does amiodarone have on P450 system?

Answer 13

P450 inhibitor

Question 14

What effect does allopurinol have on P450 system?

Answer 14

P450 inhibitor

Question 15

What effect do imidazoles (ketoconazole, fluconazole) have on P450 system?

Answer 15

P450 inhibitor

Question 16

What effect do SSRIs (fluoxetine, sertraline) have on P450 system?

Answer 16

P450 inhibitor

Question 17

What effect does ritonavir have on P450 system?

Answer 17

P450 inhibitor

Question 18

What effect does sodium valproate have on P450 system?

Answer 18

P450 inhibitor

Question 19

What effect does acute alcohol intake have on P450 system?

Answer 19

P450 inhibitor

Question 20

What effect does quinupristin have on P450 system?

Answer 20

P450 inhibitor