Ocular dysfunctions and toxicities induced by antiepileptic medications: Types, pathogenic mechanisms, and treatment strategies

Expert Rev Clin Pharmacol. 2019 Apr;12(4):309-328. doi: 10.1080/17512433.2019.1591274. Epub 2019 Mar 20.

Abstract

Ocular dysfunctions and toxicities induced by antiepileptic drugs (AEDs) are rarely reviewed and not frequently received attention by treating physicians compared to other adverse effects (e.g. endocrinologic, cognitive and metabolic). However, some are frequent and progressive even in therapeutic concentrations or result in permanent blindness. Although some adverse effects are non-specific, others are related to the specific pharmacodynamics of the drug. Areas covered: This review was written after detailed search in PubMed, EMBASE, ISI web, SciELO, Scopus, and Cochrane Central Register databases (from 1970 to 2019). It summarized the reported ophthalmologic adverse effects of the currently available AEDs; their risks and possible pathogenic mechanisms. They include ocular motility dysfunctions, retinopathy, maculopathy, glaucoma, myopia, optic neuropathy, and impaired retinal vascular autoregulation. In general, ophthalmo-neuro- or retino-toxic adverse effects of AEDs are classified as type A (dose-dependent), type B (host-dependent or idiosyncratic) or type C which is due to the cumulative effect from long-term use. Expert opinion: Ocular adverse effects of AEDs are rarely reviewed although some are frequent or may result in permanent blindness. Increasing knowledge of their incidence and improving understanding of their risks and pathogenic mechanisms are crucial for monitoring, prevention, and management of patients' at risk.

Keywords: Antiepileptic drugs; gamma-aminobutyric acid (GABA); glaucoma; glutamate; myopia; nystagmus; ocular toxicity; sodium channels; visual field defects.

Publication types

  • Review

MeSH terms

  • Animals
  • Anticonvulsants / administration & dosage
  • Anticonvulsants / adverse effects*
  • Blindness / chemically induced*
  • Blindness / epidemiology
  • Disease Progression
  • Dose-Response Relationship, Drug
  • Eye Diseases / chemically induced*
  • Eye Diseases / epidemiology
  • Eye Diseases / physiopathology
  • Humans
  • Time Factors

Substances

  • Anticonvulsants