Background: Topiramate is an antiepileptic drug used for treating migraines. Its basic important precautions include the occurrences of acute angle closure glaucoma and acute myopia. Here we report a patient who showed these adverse conditions in both eyes.
Case: A 41-year-old woman developed acute bilateral myopia 1 week after oral administration of topiramate, sodium valproate, and clonazepam was initiated for migraines. The intraocular pressure was 34 mmHg in the right eye (OD) and 35 mmHg in the left eye (OS). The refractive power (spherical equivalent) was -6.00 D OD and -5.50 D OS. The anterior chamber depth (ACD) was 2.29 mm OD and 2.27 mm OS. The lens thickness (LT) was 4.01 mm OD and 3.97 mm OS. Anterior segment optical coherence tomography (OCT) revealed anterior deviations of the lens and iris. Intraocular pressure was normalized 5 days after discontinuing the administration of multiple antiepileptic drugs, and myopia had recovered. ACD was 3.44 mm OD and 3.45 mm OS, and LT was 3.83 mm OD and 3.84 mm OS; both values showed improvements.
Conclusions: It is estimated that the forward movement of the lens-iris diaphragm was due to choroidal effusion induced by topiramate through carbonic anhydrase inhibition. Nevertheless, interactions with other antiepileptic drugs cannot be ruled out. These findings suggest that careful medical interrogations are necessary to clarify the use of drugs for systemic diseases among middle-aged patients presenting with acute angle closure glaucoma.
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 125: 1104-1109, 2021.