title: Dose-response study of dapiprazole HCl in the reversal of mydriasis induced by 2.5% phenylephrine.
abstract: Dapiprazole HCL is currently available in the United States for reversal of diagnostic mydriasis. The recommended dosage for this indication is 2 drops followed 5 minutes later by 2 drops. We studied the dose-response profile and tolerance of three different treatment regimens: 1 drop alone, 1 drop followed by 1 additional drop 5 minutes later, and 2 drops followed by 2 additional drops 5 minutes later. Sixty normal male and female volunteers between 18 and 40 years of age were recruited for a double-masked, placebo-controlled, crossover study in which each eye of each subject was dilated with 2.5% phenylephrine. After one hour, one eye was treated with 0.5% dapiprazole, and the contralateral eye was treated with placebo. Each subject was treated with each of the three dapiprazole regimens in three different study sessions separated by at least 5 days (drug half-life in the eye is 5 hours). Analysis of AUC demonstrated no significant difference (P = 0.620) between the 1 drop regimen and the 2 + 2 regimen. A single drop of dapiprazole has a clinical effect equivalent to the 2 + 2 drop regimen in eyes dilated with 2.5% phenylephrine, which should improve the cost-effectiveness of this mydriolytic agent.
authors.affiliation: Department of Optometry, School of Optometry, University of Alabama at Birmingham, USA.
authors.forename: T S
authors.initials: TS
authors.lastname: Hogan
authors.forename: D D
authors.initials: DD
authors.lastname: McDaniel
authors.forename: J D
authors.initials: JD
authors.lastname: Bartlett
authors.forename: K K
authors.initials: KK
authors.lastname: Hart
authors.forename: D A
authors.initials: DA
authors.lastname: Paggiarino
mesh_terms: D000065:Accommodation, Ocular / Q000187:drug effects* / Q000502:physiology; D000293:Adolescent; D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage* / Q000009:adverse effects; D000328:Adult; D019540:Area Under Curve; D003229:Conjunctival Diseases / Q000139:chemically induced; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000139:chemically induced; D008297:Male; D009184:Mydriatics / Q000008:administration & dosage*; D009883:Ophthalmic Solutions; D010656:Phenylephrine / Q000008:administration & dosage*; D010879:Piperazines; D011680:Pupil / Q000187:drug effects* / Q000502:physiology; D014230:Triazoles / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D000317:Adrenergic alpha-Antagonists; D009184:Mydriatics; D009883:Ophthalmic Solutions; D010879:Piperazines; D014230:Triazoles; D010656:Phenylephrine; C035289:dapiprazole