If tacrolimus ointment causes arrhythmia during use, it is recommended to stop the medication for observation and seek prompt medical attention. Tacrolimus Ointment is unlikely to cause arrhythmia as a side effect, with the incidence of this side effect being less than 1% in clinical trials. If discomfort such as arrhythmia occurs during use, discontinue the medication and observe if the discomfort persists. If the arrhythmia does not improve after stopping the medication, it is important to seek medical attention to find out if the arrhythmia is related to the medication or if there is a disease of the heart itself. Tacrolimus is contraindicated in patients with a history of hypersensitivity to tacrolimus or any other ingredient in the preparation. Tacrolimus Ointment as a topical ointment should be used strictly and accurately in accordance with the requirements of the doctor, and any discomfort during its use should be treated promptly by a doctor.