Correct match of drug and its metabolic enzyme are all except?
A. Digoxin – P glycoprotein
B. Simvastatin – Glucuronidation
C. Verapamil – CYP3A4
D. Carvedilol- CYP2D6
Correct answer : B. Simvastatin – glucuronidation (Simvastatin is metabolised by CYP2D6 – refer table given below)
Molecular Pathways Mediating Drug Disposition
Molecule Substrates Inhibitors
CYP3A Calcium channel blockers
Antiarrhythmics (lidocaine, quinidine, mexiletine)
HMG-CoA reductase inhibitors (statins)
Cyclosporine, tacrolimus
Indinavir, saquinavir, ritonavir Amiodarone
Ketoconazole, itraconazole
Erythromycin, clarithromycin
Ritonavir
CYP2D6 Timolol, metoprolol, carvedilol
Phenformin
Codeine
Propafenone, flecainide
Tricyclic antidepressants
Fluoxetine, paroxetine Quinidine (even at ultra-low doses)
Tricyclic antidepressants
Fluoxetine, paroxetine
CYP2C9 Warfarin
Phenytoin
Glipizide
Losartan Amiodarone
Fluconazole
Phenytoin
CYP2C19 Omeprazole
Mephenytoin
Clopidogrel Omeprazole
Thiopurine S-methyltransferase 6-Mercaptopurine, azathioprine
N-acetyltransferase Isoniazid
Procainamide
Hydralazine
Some sulfonamides
UGT1A1 Irinotecan
Pseudocholinesterase Succinylcholine
P-glycoprotein Digoxin
HIV-protease inhibitors
Many CYP3A substrates Quinidine
Amiodarone
Verapamil
Cyclosporine
Itraconazole
Erythromycin
Ref: Harrison 18th, chapter 5 : Table 5-1