【Abstract】 Background Rapid arrhythmias in emergency settings, particularly atrial fibrillation and ventricular tachycardia, often pose a threat to patients’ lives and require timely intervention. Amiodarone injection, as an antiarrhythmic medication, has been widely used in emergency treatment. Objective This study aims to evaluate the shortterm efficacy and adverse reactions of amiodarone injection in emergency patients with rapid arrhythmias, providing evidence for clinical treatment. Methods This retrospective study analyzed the clinical data of 80 patients with rapid arrhythmias admitted to the emergency department of the Fourth Affiliated Hospital of Nanjing Medical University from January 2019 to December 2022. All patients received amiodarone injection during the emergency phase, and its efficacy and adverse reactions were monitored. The study primarily assessed changes in patients’ electrocardiograms (ECGs), brain natriuretic peptide (BNP) levels, myocardial injury markers (e.g., troponin, creatine kinase), and the combined effect of digoxin injection. Results Among the 80 patients, 72 (90%) achieved normal heart rhythm, with ECGs demonstrating effective control of atrial fibrillation or ventricular tachycardia. After treatment, BNP levels significantly decreased, and myocardial injury markers (e.g., troponin and creatine kinase) showed marked improvement. The incidence of adverse reactions was 7.5%, mainly presenting as mild hypotension and gastrointestinal discomfort. Conclusion Amiodarone injection demonstrates significant short-term efficacy in emergency patients with rapid arrhythmias, effectively restoring heart rhythm, improving myocardial ischemia, and reducing BNP levels. With a low incidence of adverse reactions, it is suitable as a first-line treatment in emergency settings. However, treatment plans should be tailored to individual patients to avoid potential adverse effects.