Drug-induced toxic optic neuropathy

Abstract

Drug-induced optic neuropathy is a group of disorders in which medications cause degeneration of the optic nerve. The true prevalence of drug-induced neuropathy has not been studied, although the percentage of patients who develop optic nerve damage is known for individual medications. The common pathophysiological mechanisms are believed to be mitochondrial damage and imbalance of intracellular and extracellular free radical homeostasis. Typical symptoms of drug-induced neuropathy are reduced visual acuity in the central area, which is often bilateral, visual field disturbances, dyschromatopsia, and edema of the optic nerve head. Early detection of drug-induced optic neuropathy can potentially prevent or minimize serious complications. For patients who develop drug-induced optic neuropathy, treatment is based on timely diagnosis and cancellation of the provoking drug. In most patients, vision usually recovers a few weeks or months after discontinuation of previous therapy, but there have been cases of irreversible vision loss. In addition to withdrawal of the drug that caused optic nerve lesion, treatment of drug-induced neuropathy may include use of drugs and treatment methods prescribed by neurologists for peripheral neuropathy, however, such treatment is seldom based on evidence.