Toxicity from cardiac drugs is a particular management challenge since the manifestations of an acute overdose and the initial indications for the drug are often similar. Plasma drug levels are essential but must be interpreted in light of the clinical picture. Hypotension, due to either vasodilatation or decreased myocardial contractility, and arrhythmias are the principal cardiac manifestations, but noncardiac effects are sometimes more troublesome. An antiarrhythmic agent of the same class should not be used in treating an arrhythmia resulting from an overdose.
心脏药物中毒是一个特殊的管理挑战，因为急性过量用药的表现与该药物的初始适应证往往相似。血浆药物水平至关重要，但必须结合临床情况进行解读。由于血管扩张或心肌收缩力下降导致的低血压以及心律失常是主要的心脏表现，但非心脏效应有时更棘手。同一类别的抗心律失常药物不应用于治疗过量用药引起的心律失常。
