CYP 450 Inhibitors, Inducers, substrates

Question 1

CYP 450 inducers ____ the metabolism of warfarin and therefore ____ it’s effect.

Answer 1

Increase the metabolism of warfarin therefore decreasing its effect.

Question 2

Chronic alcohol consumption leads to CYP 450 induction or inhibition?

Answer 2

Alcohol causes induction of CYP 450, increasing metabolism of CYP 450 metabolized drugs.

Question 3

This flower has the ability to induce CYP450

Answer 3

St. John’s Wort

Question 4

Acute alcohol consumptions is associated with CYP450 induction or inhibition?

Answer 4

Inhibition

Question 5

What two anti-fungals cause CYP 450 inhibition

Answer 5

Fluconazole, ketoconazole.

Question 6

Sulfonamides are commonly prescribed for prophylactic treatment in HIV patients with a CD4 count <200. If a patient is on warfarin, what must you monitor?

Answer 6

INR, sulfonamides are CYP450 inducers increasing the half life of warfarin.

Question 7

In addition to sulfonamides, what additional four classes of anti-microbials are associated with CYP450 inhibition?

Answer 7

Ciprofloxacin, metronidazole, macrolides and chloramphenicol.

Question 8

Proton pump inhibitor

Answer 8

CYP 450 inhibitor

Question 9

What drug in active TB treatment inhibits CYP450?

Answer 9

Isoniazid

Question 10

What drug used in active TB treatment is a CYP 450 inducer?

Answer 10

Rifampin

Question 11

What histamine receptor 2 blocker is associated with CYP450 inhibition?

Answer 11

Cimetidine, all the -tidines.

Question 12

What are the four CYP450 substrates?

Answer 12

warfarin, theophylline, OCPs, and anti-epileptics

Question 13

What anti-epileptic is a CYP450 inducer?

Answer 13

phenytoin

Question 14

Which barbiturate must you watch out for if your patient is on warfarin?

Answer 14

Phenobarbital, CYP450 inducer; increases metabolism of warfarin decreasing its effects.

Question 15

This drug is first line treatment for trigeminal neuralgia, its also used to treat focal seizures, and is a CYP450 inducer

Answer 15

Carbamazapine

Question 16

This drug is commonly used to treat dermatophytosis caused by tinea or ringworm; by it interrupts microtubule function thereby interrupting mitosis.

Answer 16

Griseofulvin

Question 17

This non-nucleoside reverse transcriptase inhibitor is commonly used in the treatment of HIV and is a CYP450 inhibitor

Answer 17

Nevirapine.