Quinidine Mephenytoin

Genetic polymorphisms in CYP450 isoenzymes are common. Among whites, 5-10% of the population carries a mutation of CYP450 2D6, causing them to be slow metabolizers of debriso-quine, mephenytoin, quinidine, metoprolol and dextromethorphan standard doses are more likely to be associated with adverse events as a consequence, especially when a second substrate drag is interacting. 

Values were back calculated from actual in vivo DDI data for fluconazole and S-warfarin (fee, CYP2C9 = 0.91), fluvoxamine and theophylline (fcL,CYPiA2 = 0.8), fluvoxamine and S-mephenytoin (fcL,CYP2C9 = 1). ketoconazole and midazolam fcL,CYP3A,hepatic = 0.93), and quinidine and desipramine (fcL,CYP2D6 = 0.9). 

C19 2D6 Mephenytoin (4-hydroxy metabolite), Omeprazole Bufuralol, Dextromethorphan Metoprolol, Debrisquine, Codeine Tranylcypromine Quinidine Ticlopidine (but also inhibits 2D6), Nootkatone (but also inhibits 2A6)... 

Clinically important, potentially hazardous interactions with alfuzosin, alprazolam, amphotericin B, anisindione, antacids, aprepitant, astemizole, atorvastatin, bosentan, ciclesonide, cimetidine, clorazepate, conivaptan, cyproterone, dasatinib, dexamethasone, dicumarol, didanosine, eplerenone, erythromycin, ethotoin, fentanyl, fesoterodine, fosamprenavir, fosphenytoin, grapefruit juice, HMG-CoA reductase inhibitors, imatinib, ixabepilone, lapatinib, lopinavir, lovastatin, mephenytoin, methylprednisolone, micafungin, midazolam, nilotinib, pimozide, prednisolone, prednisone, quinidine, rifampin, rimonabant, rivaroxaban, sildenafil, silodosin, simvastatin, sirolimus, solifenacin, temsirolimus, terfenadine, tolvaptan, triazolam, vardenafil, vinblastine, vincristine, warfarin... 

Also analyzed acebutolol, acepromazine, acetaminophen, acetazolamide, acetophenazine, albuterol, amitriptyline, amobarbital, amoxapine, antipsrrine, atenolol, atropine, azata-dine, baclofen, benzocaine, bromocriptine, brompheniramine, brotizolam, bupivacaine, buspirone, butabarbital, butalbital, caffeine, carbamazepine, cetirizine, chlorqyclizine, chlordiazepoxide, chlormezanone, chloroquine, chlorpheniramine, chlorpromazine, chlorpropamide, chlorprothixene, chlorthalidone, chlorzoxazone, cimetidine, cisapride, clomipramine, clonazepam, clonidine, clozapine, cocaine, codeine, colchicine, qyclizine, (yclo-benzaprine, dantrolene, desipramine, diazepam, diclofenac, diflunisal, diltiazem, diphenhydramine, diphenidol, dipheno late, dipyridamole, disopyramide, dobutamine, doxapram, doxepin, droperidol, encainide, ethidium bromide, ethopropazine, fenoprofen, fentanyl, flavoxate, fluoxetine, fluphenazine, flurazepam, flurbiprofen, fluvoxamine, fii-rosemide, glutethimide, glyburide, guaifenesin, haloperidol, homatropine, hydralazine, hydrochlorothiazide, hydrocodone, hydromorphone, hydro g chloroquine, hydroxyzine, ibuprofen, imipramine, indomethacin, ketoconazole, ketoprofen, ketorolac, labetalol, le-vorphanol, lidocaine, loratadine, lorazepam, lovastatin, loxapine, mazindol, mefenamic acid, meperidine, mephenytoin, mepivacaine, mesoridazine, metaproterenol, methadone, methdilazine, methocarbamol, methotrexate, methotrimeprazine, methoxamine, methyl-dopa, methylphenidate, metoclopramide, metolazone, metoprolol, metronidazole, midazolam, moclobemide, morphine, nadolol, nalbuphine, naloxone, naphazoline, naproxen, nifedipine, nizatidine, norepinephrine, nortriptyline, oxazepam, oxycodone, oxymetazo-line, paroxetine, pemoline, pentazocine, pentobarbital, pentoxifylline, perphenazine, pheniramine, phenobarbital, phenol, phenolphthalein, phentolamine, phenylbutazone, phenyltoloxamine, phenytoin, pimozide, pindolol, piroxicam, pramoxine, prazepam, prazosin, probenecid, procainamide, procaine, prochlorperazine, procyclidine, promazine, promethazine, propafenone, propantheline, propiomazine, propofol, propranolol, protriptyline, quazepam, quinidine, quinine, racemethorphan, ranitidine, remoxipride, risperidone, salicylic acid, scopolamine, secobarbital, sertraline, sotalol, spironolactone, sulfinpyrazone, sulindac, temazepam, terbutaline, terfenadine, tetracaine, theophylline, thiethyl-perazine, thiopental, thioridazine, thiothixene, timolol, tocainide, tolbutamide, tolmetin, trazodone, triamterene, triazolam, trifluoperazine, triflupromazine, trimeprazine, trimethoprim, trimipramine, verapamil, warfarin, xylometazoline, yohimbine, zopiclone... 

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