Topiramate-induced angle closure glaucoma in a case of chronic migraine

Abstract

Topiramate is an oral sulfamate medication used primarily for epilepsy and migraine. The tolerability profile with its lack of significant metabolic side effects makes it a favorable drug for patients with comorbid lifestyle illnesses. Topiramate-induced angle closure is an idiosyncratic reaction and can occur in otherwise normal eyes with normal anterior chamber angles. Ocular examination before starting topiramate cannot identify eyes at risk. Prompt cessation of therapy alone can result in rapid resolution of most of these adverse effects, whereas failure to recognize can lead to permanent visual problems. The internists should be aware of the documented side effects of topiramate, particularly when presented with simultaneous bilateral acute angle-closure glaucoma. Neurologists initiating therapy with topiramate should also educate the patients of its potential side effects and importance of reporting back immediately in case of any visual disturbance. Prompt cessation of topiramate is the mainstay of treatment. Supportive treatment in the form of oral and topical antiglaucoma drugs to reduce the intraocular pressure (IOP), topical steroids to bring down the inflammation, and topical cycloplegics to retract the ciliary processes thus bringing down the IOP has been recommended, but a few would warrant laser iridotomy or surgical iridectomy. We report a case of topiramate-induced angle closure glaucoma in a young female being managed as a case of chronic migraine, highlighting the importance of increasing the awareness of this rare, idiosyncratic adverse effect of topiramate and the need for timely intervention to avoid irreversible visual loss.