Rabbit and human corneal epithelium was studied in tissue cultures for the effects of a variety of topically administered antiglaucoma drugs at 0.001% of their commonly prescribed concentrations. The evolution of degenerative changes was observed using different therapeutic agents and controls. In the selected concentrations tested, the strongest cytotoxic effects were produced by neostigmine bromide (Prostigmine) and carbachol (Isopto Carbachol); epinephrine and echothiophate (Phospholine) iodide were slightly less damaging. Intermediate degrees of toxicity were shown by guanethidine sulfate and a preparation of pilocarpine hydrochloride with epinephrine (P1E1) Demecarium bromide (Humorsol) and pilocarpine were least toxic. Preparations containing epinephrine produced pigment deposition. Methylcellulose (Methulose), edetate disodium, and commonly used preservatives showed no adverse effects in comparison with untreated control cultures. The results may help in choosing the least toxic drugs for topical application to glaucomatous eyes complicated by abnormal corneal epithelium.
Krejci L, Harrison R. Antiglaucoma Drug Effects on Corneal EpitheliumA Comparative Study in Tissue Culture. Arch Ophthalmol. 1970;84(6):766-769. doi:10.1001/archopht.1970.00990040768015