Opioids are compounds that cause similar effects to morphine by binding to its receptors. Opioids can be synthetic, semi-synthetic, or natural and can easily bind to the receptors of opioids in order to depict their effects, which may vary depending upon the exposure of the drug and its dose. However, several side effects of opioids can also be observed, with the most crucial being their impact on the heart’s electrical activity. This review majorly focuses on opioids' impact on the prolongation of the QT curve and their arrhythmogenic susceptibility. Articles published up to the year 2022 in various databases were identified and searched with the use of keywords. Search terms included “cardiac arrhythmias,” “QT interval,” “opioids,” “opioid dependence,” and “torsade de pointes (TdP)”. These terms highlight the impact of each opioid agent on the activity of the heart on an electrocardiogram. The results of the available data depict that opioids, such as methadone, pose higher risks, even when taken in smaller amounts, and have the capability for QT interval prolongation and TdP development. A variety of opioids, i.e., oxycodone and tramadol, are considered as intermediary risk drugs and can build long QT intervals and TdP in large doses. Several other opioids are considered low-risk drugs, including buprenorphine and morphine, which lead to no production of TdP and QT interval prolongation in daily routine doses. Evidence indicates a high risk of sinus bradycardia, atrial fibrillation, cardiac block, and supra-ventricular arrhythmias in opium consumers. This literature review will play a key role in determining the association between the use of opioids and cardiac arrhythmias. It will further highlight the practical implications of opioids for the management of cardiac issues based on their dose, frequency, and intensity. Moreover, it will also depict the adverse effects of opioids along with their dose-specific relationship. Opioids display disparate cardiac arrhythmogenicity, and methadone contains a greater ability to induce long QT intervals and hazardous arrhythmias at conventional doses. In order to reduce arrhythmogenic risk, opioids taken in large amounts should be monitored with a regular electrocardiogram in high-risk consumers, i.e., patients on opioid maintenance.