Comparative pharmacologic effects of pilocarpine administered to normal subjects by eyedrops or by ocular therapeutic systems.

Normal volunteers used 1, 2, and 4% pilocarpine eyedrops, three times daily, or ocular therapeutic systems placed in the conjunctival cul-de-sac to control intraocular pressure. The systems continuously release 20 and 40 mug/hour of pilocarpine for one week. Although the amount of drug delivered to the eye from the ocular therapeutic system was one fifth that obtained from the eyedrops, the decrease of intraocular pressure was comparable. The ocular therapeutic systems produced small, constant effects on visual acuity, refractive error, and miosis that did not cause visual handicaps or require correction. The effects of eyedrops on these visual factors were large and varied and produced marked visual handicaps that were not correctable with spectacles. Despite its comparable hypotensive effect in normal subjects, continuous delivery of pilocarpine by means of an ocular therapeutic system elicits less severe side effects than pilocarpine eyedrops.