Background The aim is to compare the use of adenosine and verapamil for management of postoperative supraventricular tachycardia in terms of time of conversion of SVT to normal sinus rhythm, success rate, hospital stay length and adverse eventsMethods Patients (54–65 years old) received adenosine or verapamil groups. In the adenosine group, patients received IV adenosine 6 mg bolus then wait 2 minutes, if it failed another 12 mg IV of adenosine was administered. In the verapamil group, patients received IV verapamil 5mg bolus slowly over 2 minutes followed by a second IV bolus of 10 mg, 30 minutes after the initial dose in persistent supraventricular tachycardia (SVT). If SVT persisted, the patient was shifted to adenosine. Results Patients were followed up regarding the efficacy of drug, blood pressure, mean time of conversion of SVT (time elapsed from effective dose of the study drug till conversion of SVT to sinus rhythm) and incidence of adverse events were recorded. The efficacy of adenosine was significantly higher than verapamil (P <0.001). The time of conversion of SVT to sinus rhythm was significantly shorter in adenosine group compared with verapamil group (P < 0.001). The incidence of hypotension was comparable between the study groups. The mean arterial blood pressure and the incidence of complications were comparable.Conclusions Intravenous administration of adenosine effectively treat SVT in terms of higher efficacy and shorter time of conversion of SVT to normal sinus rhythm compared with verapamil without any significant difference regarding the incidence of side effects between the study groups.Trial registrationThis study was approved by Medical ethics committee of Ain Shams University approval number FMASU R 62/ 2019). and the protocol was prospectively registered at ClinicalTrials.gov : NCT 04203368 on December 16, 2019.