Gatifloxacin Amiodarone

Concurrent use of the fluoroquinolones with theophylline causes an increase in serum theophylline levels. When used concurrently with cimetidine, the cimetidine may interfere with the elimination of the fluoroquinolones. Use of the fluoroquinolones with an oral anticoagulant may cause an increase in the effects of the oral coagulant. Administration of the fluoroquinolones with antacids, iron salts, or zinc will decrease absorption of the fluoroquinolones. There is a risk of seizures if fluoroquinolones are given with the NSAIDs. There is a risk of severe cardiac arrhythmias when the fluoroquinolones gatifloxacin and moxifloxacin are administered with drains that increase the QT interval (eg, quini-dine, procainamide, amiodarone, and sotalol). 

Adenosine 3-Blockers Amiodarone Carbamazepine Chloroquine Digoxin Diltiazem Gatifloxacin... 

Cardiac toxicity Moxifloxacin and gatifloxacin have been shown to prolong the QT interval of the electrocardiogram in some patients. Avoid in patients with known prolongation of the QT interval, patients with uncorrected hypokalemia, and patients receiving class lA (eg, quinidine, procainamide) or class III (eg, amiodarone, sotalol) antiarrhythmic agents. 

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... 

Torsade de pointes has been reported in two patients taking amiodarone and levofloxacin. Post-marketing surveillance identifled two cases with amiodarone and sparfloxacin. An increased risk of this arrhythmia would also be expected if amiodarone is used with gatifloxacin or moxifloxacin. 

Amiodarone can prolong the QT interval and increase the risk of torsade de pointes. Of the quinolones used clinically, gatifloxacin, moxifloxacin, and sparfloxacin are known to prolong the QT interval (see Table 9.2 , (p.257)). There is also evidence that levofloxacin may prolong the QT in-terval. ... 

---