s a sulfamate-substituted monosaccharide, Topiramate is mainly used in the treatment of epilepsy, prophylaxis of migraine, bipolar affective disorder, and eating disorders. Even though some side effects of topiramate has been reported in the literature, it is the first case of a patient developing high angle myopia without angle-closure glaucoma, due to use of topiramate. A 22-year-old female patient complained of sudden onset of blurred vision for two days. Oral topiramate treatment had been commenced for migraine prophylaxis 7 days prior to her complaints. On ophthalmologic examination, her visual acuity was noted as -10.00 with myopic correction 6/10 for the right eye and -9.00 with myopic correction 6/10 for the left eye. She had no refraction abnormalities or complaints before the treatment. With the Ultrasonographic Biomicroscopy suprachoroidal effusion was observed at ora serrata and under silier body. Following the second day of the discontinuation of the drug, all symptoms and complaints resolved. Ocular side effects of topiramate have been reported in the literature but it is the first time ultrasonographic biomicroscopy is used in order to understand the underlying mechanism. Because discontinuation of topiramate is enough in order to relieve rapidly onset of visual loss, clinicians should be aware of this side effect of topiramate.