Background: Amiodarone is a third-class antiarrhythmic drug used to treat a number of heart conditions such as ventricular and supraventricular arrhythmias and atrial fibrillation. Like any other drug, it has side effects, the most important of which are ocular side effects such as inflammation of the optic nerve, impaired vision, the appearance of deposits on the corneal epithelium and visual loss.

Aim: To evaluate the amiodarone toxic effect on the visual pathway by visual evoked potential stimulation using checkerboard pattern.

Methods: In this study, 25 patients treated with amiodarone who had visual impairment (blurred vision, seeing a colored ring around the light) were referred to Basir Eye Clinic were randomly selected, p100 latency (in milliseconds) and amplitude (in microvolts) measured in them and compared with 25 patients as a control group from April 2019 to March 2020.

Results: The mean latency of p100 wave in the case group was 116.9 and in the control group was 99.7 which showed a statistically significant difference between the two groups (P <0.001). Also the mean amplitude recorded in case group was 2.2 and in the control group was 6.1 which showed a statistically significant difference between the two groups (P <0.001).

Conclusion: this is inferred that amiodarone has a significant effect on the optic nerve pathway, which is detected by the visual evoked potential based on the decreasing amplitude index and increasing p100 wave latency.

Keywords: visual evoked potential, amiodarone, checkerboard pattern.