Metronidazole為經常被用於厭氧菌感染的抗微生物製劑，過去曾有罕見導致視神經病變的案例報告，文獻上並未明確指出藥物引起視神經病變的症狀、發生頻率以及預後，但少數案例報告指出，本藥引起之視覺障礙包含視野缺損、近視、畏光、視神經炎及轉眼危象。本案例為一70歲女性，10年第二型糖尿病病史，被診斷罹患增生性糖尿病視網膜病變，此次因陰部感染至婦產科就診，醫師處方metronidazole，治療10天後突發性失明，經眼科及神經科醫師檢查後，診斷為藥物引起之毒性視神經病變，造成病人永久性失明。
 

Metronidazole has been approved to treat infection. Little is known about the cases of drug-induced optic neuropathy. Literature does not clearly indicate the symptoms, frequency and prognosis of drug-induced optic neuropathy, but there were several case reports of visual impairment caused by metronidazole including visual field defect, myopia, photophobia, optic neuritis and oculogyric crises. This case is a 70-year-old female with a 10-year history of type 2 diabetes, and proliferative diabetic retinopathy. The patient received etronidazole for treatment of her leukorrhea. She had been noted bilateral visual impairment and this became progressively worse even occurrence of sudden blindness. Symptoms began 10 days after initiation of metronidazole therapy. Ophthalmic and neurological examinations were performed to determine the cause of her blindness, and test results favored drug-induced toxic optic neuropathy as the cause of permanent blindness of this patient.