Clinical evidence,mechanism, importance and management
A retrospective study,covering a 6-year period in 29 hospitals, identified 29 patients (27 available for review) who received lidocaine for prophylaxis or treatment of cocaine-associated myocardial infarction. No patient exhibited bradycardia,sustained ventricular tachycardia or ventricular fibrillation, and no patients died (See reference number 1).
Both lidocaine and cocaine exhibit class I antiarrhythmic effects and are proconvulsants. Lidocaine may potentiate cardiac and CNS adverse effects of cocaine. Therefore use of lidocaine for cocaine-associated myocardial infarction is controversial. The lack of adverse effects in this study may have been due to delays of more than 5 hrs between last exposure to cocaine and lidocaine therapy. These authors(See reference number 1) and others(See reference number 2,3) consider that cautious use of lidocaine does not appear to be contraindicated in patients with cocaine-associated myocardial infarction who require antiarrhythmic therapy. However,extra care should be taken in patients who receive lidocaine shortly after cocaine (See reference number 1).
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