title: Changes in pupil diameter after oral administration of codeine.
abstract: Pupillary constriction occurs following administration of opioids and may be used as a marker of opioid activity. We have measured plasma concentrations and pupil diameters in 16 healthy volunteers after the oral administration of placebo or codeine. Pupil size decreased significantly after codeine compared with placebo. Pupil size was related to the plasma concentrations of codeine (P less than 0.05).
authors.affiliation: University Department of Anaesthesia, University of Sheffield Medical School.
authors.forename: J E
authors.initials: JE
authors.lastname: Peacock
authors.forename: P D
authors.initials: PD
authors.lastname: Henderson
authors.forename: W S
authors.initials: WS
authors.lastname: Nimmo
mesh_terms: D000284:Administration, Oral; D000328:Adult; D003061:Codeine / Q000097:blood / Q000494:pharmacology*; D006801:Humans; D011680:Pupil / Q000187:drug effects*; D013997:Time Factors
chemical_list: D003061:Codeine