Procainamide with quinolones

Of the quinolones used clinically, gatifloxacin, moxifloxacin, and sparfloxacin are known to prolong the QT interval (see Table 9.2 , (p.257)) and would be expected to increase the risk of torsade de pointes arrhythmias when used with procainamide. These quinolones should probably be avoided in patients on procainamide (see also Drugs that prolong the QT interval + Other drugs that prolong the QT interval , p.257). 

One case of torsade de pointes was noted in a patient taking procainamide with a quinolone [unspecified] in an analysis of cases of torsade de pointes associated with quinolones on the FDA Adverse Events Reporting... 

PROPAFENONE I. ANTIARRHYTHMICS - disopyra-mide, procainamide 2. ANTIBIOTICS - macrolides (especially azithromycin, clarithromycin, parenteral erythromycin, telithromycin), quinolones (especially moxifloxacin), quinupristin/ dalfopristin 3. ANTICANCER AND IMMUNOMODULATING DRUGS -arsenic trioxide 4. ANTIDEPRESSANTS - TCAs, venlafaxine 5. ANTIEMETICS-dolasetron 6. ANTIFUNGALS-fluconazole, posaconazole, voriconazole 7. ANTIHISTAMINES - terfenadine, hydroxyzine, mizolastine 8. ANTI-M ALARIALS - artemether with lumefantrine, chloroquine, hydroxychloroquine, mefloquine, quinine 9. ANTIPROTOZOALS - pentamidine isetionate 10. ANTIPSYCHOTICS-atypicals, phenothiazines, pimozide II. BETA-BLOCKERS - sotalol 12. BRONCHODILATORS -parenteral bronchodilators 13. CNS STIMULANTS - atomoxetine Risk of ventricular arrhythmias, particularly torsades de pointes Additive effect these drugs prolong the Q-T interval. Also, amitriptyline, clomipramine and desipramine levels may be t by propafenone. Amitriptyline and clomipramine may t propafenone levels. Propafenone and these TCAs inhibit CYP2D6-mediated metabolism of each other Avoid co-administration... 

Clinically important, potentially hazardous interactions with abacavir, amiodarone, bretylium, chlorpromazine, ciprofloxacin, disopyramide, enoxacin, fluphenazine, gatifloxacin, lomefloxacin, mesoridazine, moxifloxacin, norfloxacin, ofloxacin, phenothiazines, procainamide, prochlorperazine, promethazine, quinidine, quinolones, sotalol, sparfloxacin, thioridazine, trifluoperazine... 

Leukopenia, eosinophilia, and mild elevations in serum transaminases occur rarely. Prolongation of the QT interval has been observed with sparfloxacin and to a lesser extent with gati-floxacin and moxifloxacin. Quinolones probably should be used only with caution in patients who are taking certain antiarrhythmics, including amiodarone, quinidine, and procainamide (see Chapter 34). 

Ofloxacin and levofloxacin cause moderate increases in the serum levels of procainamide, whereas ciprofloxacin has a lesser effect However, the ECG appears to be unaltered in studies in healthy subjects given these quinolones with procainamide. An increased risk of torsade de pointes would be expected if procainamide is used with gatifloxacin, moxifloxacin, or sparfloxacin, and possibly levofloxacin. 

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