Bilateral optic neuritis evolved during tamoxifen treatment.

A 57-year-old woman developed bilateral optic neuritis after being treated for 6 months with tamoxifen in the dosage of 30 to 40 mg orally a day. As the neuritis progressed during continued treatment and no other causal explanation could be found, tamoxifen was stopped and the optic neuritis regressed. Since tamoxifen might cause optic neuritis the authors recommend the monitoring of ocular symptoms in treated patients.