[A combination of 1% guanethidine and 0.2% epinephrine in drop form to lower IOP in open-angle glaucoma (author's transl)].

Topical administration of guanethidine leads to a "chemical postganglionic sympathectomy" that causes a hypersensitivity to epinephrine in the eye. Therefore, even low concentrations of epinephrine added to guanethidine lower intraocular pressure efficiently in cases of open-angle glaucoma. In order to test the feasibility of a therapy with both low dosages and minimal effective concentrations, at the same time avoiding the disadvantages of topical parasympathicomimetic treatment in normalizing intraocular pressure, a long-term study of ten patients presenting with confirmed open-angle glaucoma is being carried out. It has now been running for 15 months. A collyrium containing 1.0% guanethidine and 0.2% epinephrine is administered topically. The results and the statistical evaluation confirm a significant lowering of intraocular pressure without triggering any signs of tachyphylaxy during the whole duration of the trial. This represents a further alternative to nonmiotic treatment of open-angle glaucoma.