Effects of topical anesthetics on phenylephrine-induced mydriasis.
Pupil responses to phenylephrine alone and to phenylephrine preceded by a topical anesthetic were recorded by means of an infrared pupillometer. In response to phenylephrine, pupils dilated more in eyes with pale irides. Dilation was greater if a topical anesthetic was applied before the mydriatic. Benoxinate, proparacaine, and tetracaine produced approximately equal degrees of enhancement of the mydriasis. One drop of 1% phenylephrine had only a small dilating effect on an eye when the fellow eye received the phenylephrine preceded by 0.5% proparacaine.
D000287:Administration, Topical; D000328:Adult; D000779:Anesthetics, Local / Q000494:pharmacology*; D006801:Humans; D008875:Middle Aged; D009184:Mydriatics / Q000494:pharmacology*; D010656:Phenylephrine / Q000494:pharmacology*; D011680:Pupil / Q000187:drug effects*; D013748:Tetracaine / Q000494:pharmacology
D000779:Anesthetics, Local; D009184:Mydriatics; D013748:Tetracaine; D010656:Phenylephrine