Quinidine with amiodarone

Increased risk of QT prolongation with cisapride, droperidol, phenothi-azines, pimozide, quinidine, ranolazine, amiodarone... 

The safety of antidysrhythmic drugs in children has not been thoroughly studied. However, the risk of prolongation of the QT interval seems to be considerably less than that in adults (226), although it has been reported with quinidine, disopyramide, amiodarone, sotalol, and diphemanil. 

Interactions of mexiletine with other cardioactive drugs have been reviewed (48). The most important are beneficial interactions with beta-adrenoceptor antagonists, quinidine, and amiodarone in the suppression of ventricular tachydysrhythmias. During these interactions the... 

Clinically important, potentially hazardous interactions with amiodarone, procainamide, quinidine, sotalol... 

Clinically important, potentially hazardous interactions with amiodarone, bepridil, cisapride, disopyramide, droperidol, erythromycin, flecainide, levodopa, pentamidine, procainamide, quinidine, sotalol, sparfloxacin, terfenadine, thioridazine... 

Clinically important, potentially hazardous interactions with amiodarone, amitriptyline, amoxapine, benzodiazepines, bepridil, clomipramine, clonazepam, clorazepate, delavirdine, desipramine, diazepam, dihydroergotamine, doxepin, ergotamine, fentanyl, flurazepam, imipramine, ixabepilone, lidocaine, lorazepam, methysergide, midazolam, nortriptyline, oxazepam, phenytoin, protriptyline, quazepam, quinidine, rifampin, ritonavir, sildenafil, St John s wort, temazepam, tricyclic antidepressants, trimipramine, vitamin E... 

Clinically important, potentially hazardous interactions with amiodarone, anabolic steroids, antithyroid agents, barbiturates, bivalirudin, cimetidine, clofibrate, clopidogrel, cyclosporine, delavirdine, dextrothyroxine, disulfiram, fluconazole, glutethimide, imatinib, itraconazole, ketoconazole, metronidazole, miconazole, penicillins, phenylbutazones, piperacillin, quinidine, quinine, rifabutin, rifampin, rifapentine, rofecoxib, salicylates, sulfinpyrazone, sulfonamides, testosterone, thyroid, zileuton... 

Clinically important, potentially hazardous interactions with amiodarone, azithromycin, bepredil, bosentan, bretylium, cisapride, clarithromycin, disopyramide, erythromycin, erythromycin fluconazole, fluoxetine, fluvoxamine, grapefruit juice, indinavir, itraconazole, ketoconazole, metronidazole, miconazole, nefazodone, nilotinib, paroxetine, pimozide, probucol, procainamide, quinidine, quinine, ritonavir, saquinavir, sertraline, sotalol, SSRIs, terfenadine, troleandomycin, voriconazole, zileuton, ziprasidone... 

Clinically important, potentially hazardous interactions with amiodarone, atorvastatin, bepridil, carbamazepine, delavirdine, dihydroergotamine, etravirine, flecainide, itraconazole, ketoconazole, lidocaine, lopinavir, lovastatin, midazolam, phenobarbital, phenytoin, pimozide, propafenone, quinidine, rifabutin, rifampin, sildenafil, simvastatin, St John s wort, triazolam, vardenafil, warfarin... 

Clinically important, potentially hazardous interactions with amiodarone, amisulpride, amitriptyline, amoxapine, arsenic, bepridil, bretylium, calcium, chlorpromazine, clomipramine, desipramine, disopyramide, doxepin, erythromycin, fluphenazine, imipramine, iron salts, magnesium, mesoridazine, nortriptyline, pentamidine, perphenazine, phenothiazines, pimozide, procainamide, prochlorperazine, promazine, promethazine, protriptyline, quinidine, sotalol, sucralfate, thioridazine, tricyclic antidepressants, trifluoperazine, trimipramine, zinc salts... 

The newest type III agent, dofetihde, is effective in preventing recurrences of atrial fibrillation" but has not been compared directly with amiodarone. In a large multicenter trial," dofetihde (dose adjusted for renal function and QT interval) was more effective than placebo in maintaining sinus rhythm (about 40% to 60% at 1 year). Like sotalol and quinidine, dofetilide has significant potential to cause torsade de pointes (in a dose-related fashion), and because of this, we believe that dofetilide should not be considered first-line therapy for recurrent atrial fibrillation at this time. 

Telithromycin may cause clinically significant QTc prolongation and increased risk of ventricular arrhythmia in predisposed patients. It should not be used in patients with prolonged QT syndrome, uncorrected hypokalemia or hypomagnesemia, profound bradycardia, or in patients receiving certain antiarrhythmics (e.g., quinidine, procainamide, amiodarone) or other agents that prolong QTc (e.g., cisapride, pimozide). 

Compare the relative safety of quinidine and amiodarone with respect to their mechanisms of action. 

Class Ib antiarrhythmics are usually associated with shortening of the QT interval, and could therefore be expected to reduce the QT prolongation and risk of torsade de pointes seen with amiodarone alone (for examples of this effect of mexiletine see also Mexiletine + Beta blockers, p.268 and Mexiletine + Quinidine , p.269. However, note that the UK manufacturer of mexiletine says that it may exacerbate arrhythmias [as all antiarrhythmics may], but also that it may be used concurrently with amiodarone. The two drugs have been used together successfully. ... 

AF often recurs after initial cardioversion because most patients have irreversible underlying heart or lung disease. A metaanalysis confirmed that quinidine maintained sinus rhythm better than placebo however, 50% of patients had recurrent AF within 1 year, and more importantly, quinidine increased mortality, presumably due in part to proarrhythmia. Type Ic (e.g., flecainide, propafenone) and type III (e.g., amiodarone, sotalol, dofetilide) antiarrhythmic agents may be alternatives to quinidine however, these agents are also associated with proarrhythmia. Consequently, chronic antiarrhythmic drugs should be reserved for patients with recurrent paroxysmal AF associated with intolerable symptoms during episodes of AF. 

Congenital or acquired QTprolongation Patients with congenital QT prolongation and those taking Class lA (eg, quinidine, procainamide) or Class III (eg, amiodarone, sotalol) antiarrhythmic medications should avoid using vardenafil. 

Hypersensitivity to any component of the product. Coadministration of nelfinavir is contraindicated with drugs that are highly dependent on CYP3A for clearance and for which elevated plasma concentrations are associated with serious and/or life-threatening events (eg, amiodarone, quinidine, ergot derivatives, pimozide, midazolam, triazolam, lovastatin, simvastatin see Drug Interactions). 

Drug interactions Serious and/or life-threatening drug interactions could occur between amprenavir and amiodarone, lidocaine (systemic), tricyclic antidepressants, and quinidine. Concentration monitoring of these agents is recommended if these agents are used concomitantly with amprenavir. 

Amiodarone increases the hypoprothrombinemic response to warfarin (an oral anticoagulant) by reducing its metabolism. Patients receiving digoxin may undergo an increase in serum digoxin concentrations when amiodarone is added to the treatment regimen. Amiodarone interferes with hepatic and renal elimination of flecainide, phenytoin, and quinidine. 

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