[Toxic retinopathy caused by veterinary antiparasitic closantel: a case report]

A 32-year-old female patient presented with bilateral vision loss for 2 months following her intake of various antiparasitic drugs, including closantel, a veterinary drug, for a self-perceived intraocular parasitic infection. Swept-source optical coherence tomography revealed diffuse hyperreflectivity between the outer nuclear layer and the retinal pigment epithelium, as well as the largely indistinguishable outer retinal layers. This case was clinically diagnosed with veterinary closantel-induced toxic retinopathy and had a poor visual prognosis after nerve nutrition and circulation improvement therapy due to the long duration of the disease.