A 50-year-old diabetic man receiving insulin, and suffering from chronic hepatitis C treated with interferon alfa and ribavirin presented with an acute peripheral scotoma and retinopathy associated with interferon therapy. When the treatment was interrupted, all the clinical symptoms and the test abnormalities returned to normal. If the association of interferon alpha and ribavirin increase the incidence of retinopathy, diabetes, and hypertension are also risk factors. Therapeutic abstention and monitoring are usual in the absence of visual acuity changes. However, in certain cases, such as in this patient, ceasing treatment as a matter of urgency avoids serious visual aftereffects. However, because of the incidence on the liver disease, this treatment interruption requires having clearly ruled out all other differential diagnoses.