To the Editor.
—In a recent article entitled "Phototoxic Corneal and Lens Opacities: In Dogs Receiving a Fungicide, 2,6-Dichloro-4-Nitroaniline" (Arch Ophthal83:336, 1970), Bernstein et al state: "The only recognized drug-induced, light-related ocular reaction in humans is the melanosis of the conjunctiva (similar to the melanosis of the skin) seen with high dose, long term chlorpromazine therapy."It is well recognized that epinephrine eye drops cause pigmentation of both the conjunctiva1,2 and cornea.3-5 This pigmentation results from the fact that epinephrine is oxidized and polymerized to melanin or a melanin-like compound.5 However, none of the articles cited points out the relationship of this pigmentation to light.Epinephrine gradually browns on exposure to light and air,6 and because of this, corneal pigmentation is thought to be accelerated by light (A. P. Ferry, oral communication, May 20, 1970). This light-induced darkening of epinephrine also occurs in vitro
Bullock JD. EPINEPHRINE PIGMENTATION. Arch Ophthalmol. 1970;84(4):546. doi:10.1001/archopht.1970.00990040548029