The effect of light intensity and dose of dilute pilocarpine eyedrops on pupillary constriction in healthy subjects.

Abstract

The aim of this study was to investigate variables that influence the degree of pupillary constriction to dilute pilocarpine eyedrops in healthy control subjects. The pupillary response to 50 microliter of pilocarpine 0.0625% in darkness, dim light, and bright light was measured photographically in 15 healthy adults. Constriction to pilocarpine was greater in darkness and in dim light than in bright light, indicating that the pupillary-light reflex masked the constrictive effect of pilocarpine. In ten other subjects pupillary constriction to 50 microliters of pilocarpine 0.04%, and to 50 and 100 microliters of pilocarpine 0.0625%, was measured on separate occasions. Pupillary constriction increased in proportion to the volume and concentration of pilocarpine. Data for pupillary constriction to 50 microliters of pilocarpine 0.0625% in dim light were determined in all 25 subjects.