Propafenone Cimetidine

In addition, the US manufacturer also recommends caution if tizanidine is given with other inhibitors of CYP1A2, of which they mention amio-darone, mexiletine, propafenone, cimetidine and ticlopidine. For a list of clinically important CYP1A2 inhibitors, see Table 1.2 , (p.4). 

Are there contraindications to concomitant drug use For instance, tizanidine is contraindicated in patients with concomitant use of CYP450 1A2 inhibitors such as fluvoxamine, amiodarone, mexiletine, propafenone, cimetidine, fluoroquinolones (ciprofloxacin, norfloxacin), rofecoxib, oral contraceptives, and ticlopidine [27]. 

Chloral hydrate Chloramphenicol Cimetidine Ciprofloxacin Clofibrate Danazol Disulfiram Doxycycline Erythromycin Fenofibrate Fluconazole Fluorouracil Fluoxetine Fluvoxamine Gemfibrozil Influenza vaccine Isoniazid Itraconazole Fovastatin Metronidazole Miconazole Moxalactam Neomycin Norfloxacin Ofloxacin Omeprazole Phenylbutazone Piroxicam Propafenone Propoyxphene Quinidine Sertraline Sulfamethoxazole Sulfinpyrazone Tamoxifen Testosterone Vitamin E Zafirlukast... 

Drugs that may affect mexiletine include aluminum-magnesium hydroxide, atropine, narcotics, cimetidine, fluvoxamine, hydantoins, metoclopramide, propafenone, rifampin, urinary acidifiers, and urinary alkalinizers. 

Concurrent administration of propafenone with digoxin, warfarin, propranolol, or metoprolol increases the serum concentrations of the latter four drugs. Cimetidine slightly increases the propafenone serum concentrations. Additive pharmacological effects can occur when lidocaine, procainamide, and quinidine are combined with propafenone. 

A2 Fluvoxamine Ciprofloxacin, mexiletine, propafenone, zileuton Acyclovir, cimetidine, famotidine, norfloxacin, verapamil... 

PROPAFENONE H2 RECEPTOR BLOCKERS Cimetidine may t propafenone levels Cimetidine inhibits CYP2D6-mediated metabolism of propafenone. Ranitidine is a weak CYP2D6 inhibitor Monitor PR and BP at least weekly until stable. Warn patients to report symptoms of hypotension (lightheadedness, dizziness on standing, etc.). Consider alternative acid-suppression therapy... 

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... 

Noninterfering adenosine, albuterol, alphenal, aspirin, caffeine, carbamazepine, cefazo-lin, cephalexin, cephalothin, cimetidine, ciprofloxacin, claforan, desipramine, enoxacin, fleroxacin, furosemide, hydralazine, hydrochlorothiazide, minoxidil, norfloxacin, pheny-toin, propafenone, sulindac, teicoplanin, theophylline, vancomycin Interfering some indocyanine green impurities... 

Beyond those in vivo examples depicted in Table 4, there are some in vitro data suggesting stereoselective drug interactions with oral anticoagulants. For example, Hermans and Thijssen [68] investigated the potential of metabolic interactions in vitro between warfarin or acenocou-marol and cimetidine, propafenone, sulphaphenazole, or omeprazole using human liver microsomes. Sulphaphenazole competitively inhibited the 7- and in some experiments the 6-hydroxylation of S-warfarin and R- and S-acenocoumarol. Omeprazole partly inhibited the 6- and 7-hydroxylation of R-warfarin, R-acenocoumarol, and S-acenocoumarol [68]. 

Cimetidine appears to interact minimally with propafenone. 

A study in 12 healthy subjects (10 extensive metabolisers and 2 poor metabolisers of propafenone) given propafenone 225 mg every 8 hours found that the eoncurrent use of cimetidine 400 mg every 8 hours eaused some ehanges in the pharmacokinetics and pharmacodynamics of the propafenone, with wide intersubject variability. Raised mean peak and steady-state plasma levels were seen (24 and 22%, respectively), but these did not reach statistical significance. A slight increase in the QRS duration also occurred. However, none of the changes were considered clinically important. 

Pritchett ELC, Smith WM, Kirsten EB. Pharmacokinetic and pharmacodynamic interactions of propafenone and cimetidine. J Clin Pharmacol (1988) 28, 619-24,... 

Selertive serotonin reuptake inhibitors may decrease metabolism of alpha/beta blockers, benzodiazepines, carbamazepine, cimetidine, clozapine, fesoterodine, haloperidol, methadone, mexiletine, phenytoin, propafenone, respiradone, tamoxifen, galantamine, respiradone, thioridazine. 

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