Sparfloxacin Terfenadine

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

In order to prevent any untoward effect on cardiac repolarization, agents that prolong the QT interval, such as terfenadine, astemizole, eiythromycin, and agents with Class la and Class III antidysrhythmic activity, should not be used together with sparfloxacin (137). 

The effect of the concomitant administration of terfenadine and sparfloxacin on the QTc interval has been studied in healthy men aged 18 9 years (12). Sparfloxacin was given in a dose of 400 mg on the first day and 200 mg/day thereafter for 3 days with terfenadine 60 mg bd. Terfenadine had no effect on the pharmacokinetics of sparfloxacin and there were no apparent effects on the QTc interval. 

Morganroth J, Hunt T, Dorr MB, Magner D, Talbot GH. The effect of terfenadine on the cardiac pharmacodynamics of sparfloxacin. Chn Ther 1999 21(9) 1514-24. 

Clinically important, potentially hazardous interactions with alfentanil, aminophylline, amisulpride, amoxicillin, ampicillin, anticonvulsants, astemizole, atorvastatin, benzodiazepines, bromocriptine, buprenorphine, bupropion, carbamazepine, cilostazol, ciprofloxacin, cisapride, clindamycin, colchicine, cyclosporine, dasatinib, digoxin, dihydroergotamine, diltiazem, disopyramide, enoxacin, eplerenone, ergotamine, eszopiclone, everolimus, fluconazole, fluoxetine, fluvastatin, gatifloxacin, HMG-CoA reductase inhibitors, imatinib, itraconazole, ketoconazole, lomefloxacin, lorazepam, lovastatin, methadone, methylprednisolone, methysergide, midazolam, mizolastine, moxifloxacin, nitrazepam, norfloxacin, ofloxacin, paroxetine, pimozide, pravastatin, quinolones, ranolazine, repaglinide, rupatadine, sertraline, sildenafil, simvastatin, sparfloxacin, sulpiride, tacrolimus, terfenadine, triazolam, troleandomycin, vardenafil, verapamil, vinblastine, warfarin, zaleplon, zolpidem, zuclopenthixol... 

In a placebo-controlled study 22 patients were given sparfloxacin 400 mg on day 1 and 200 mg on days 2 to 4 with terfenadine 60 mg twice a day for 7 doses. The increase in the QT interval when the two drugs were given together was additive, and no pharmacokinetic interaction was found. ... 

Akhtar M, Saha N, Roy A, Pillai KK. Effect of sparfloxacin and terfenadine combination on QT-intervals at various RR-intervals. Inditm J Pharmacol (2002) 34,264-8. 

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