Introduction:Metronidazole is a bactericidal, amoebicidal, and trichomonacidal agent targeting anaerobic bacteria, certain amoebic and protozoal species. It is a nitroimidazole that inhibits nucleic acid synthesis by disrupting DNA resulting in strand breakage. Its bioavailability is more than 80% when taken orally. It is a usually well-tolerated antimicrobial but can cause gastrointestinal side effects like a gastric upset in the form of nausea, vomiting, abdominal cramps, diarrhea, or constipation [1]. It has also been associated with other adverse effects like dizziness, darkening of the urine, and joint pain. Disulfiram reaction has been reported, especially in those drinking ethanol. Neuro-ophthalmologic side effects such as peripheral neuropathy, ataxia, encephalopathy, and even seizures have been reported with metronidazole use[2]. Optic neuritis, an inflammation of the optic nerve, is an unrecognized side effect of Metronidazole and has been reported in association with metronidazole administration in a few case reports. The nerve damage induced by Metronidazole can be either temporary or permanent.Here, we are reporting a 30-year-old lady who had a bout of gastroenteritis and was given a dose of IV Metronidazole and one day after which she started noticing decreased right eye vision, which progressed to complete vision loss in her right eye. She was managed with IV Pulse steroids. She showed a slight improvement in her right eyesight.
