The Effect of Instillations of Ephedrine Solution Upon the Eye.

Abstract

The sudden and great popularity of ephedrine for therapeutic purposes, chiefly in connection with mucous membrane affections, seemed to us to warrant further investigations on the action of the drug upon the eye. Experimental tests with ephedrine hydrochloride (C₁₀H₁₅ON.HCl) in solutions ranging from 1 to 10 per cent, were made on the eyes of 15 individuals. It was our object to determine what effect, if any, the drug has upon the acuity of vision, the sensitivity of the ocular mucous membrane, the intraocular tension, the pupil, the range of accommodation, and in producing any other symptoms, subjective or objective. Two drops of the solution were instilled 4 times into each eye at intervals of 5 minutes. Observations were made continuously over periods of several hours.

Results—1. Vision: There was no diminution of vision, but all the subjects noticed a slight fading of the test letters, which cannot be attributed to a loss of rectinal sensitivity, but rather to a lack of definition of the letters due to the enlarged pupil.

2. Anesthesia or hyperesthesia: No diminished or increased sensitivity of the cornea and conjunctiva was observed.

3. Pupils : Mydriasis occurred in all subjects. The first evidence of dilatation of the pupil was observed as early as 7 minutes after the first instillation in one case. The mydriatic action in another case did not begin until 67 minutes. Generally the first sign was observed in 15 or 20 minutes. Maximum dilatation (about 7 mm.) was attained in the great majority of subjects in 40 to 60 minutes after the first dilatation. In one case there was only moderate mydriasis. The mydriasis lasted from 3 to 5 hours, depending somewhat, but not wholly, upon the strength of the solutions used.