Double-blind comparison of the respiratory and sedative effects of codeine phosphate and (+/-)-glaucine phosphate in human volunteers.

Publisher Website
Google Scholar
Abstract
1 Two antitussive agents (+/‐)‐glaucine phosphate and codeine phosphate have been compared with placebo with respect to ventilation, ventilatory response to carbon dioxide, pulse, blood pressure, digit symbol substitution, sedation score and the Zahlen‐Verbindung test performance in ten healthy volunteers (22‐36 years). The study was double‐blind and the two doses of each antitussive agent and the placebo were administered as a syrup. 2 Both codeine phosphate and (+/‐)‐glaucine phosphate displaced the ventilatory response to carbon dioxide to the right. 3 The effect of codeine phosphate on the ventilatory response to carbon dioxide was not dose dependent: 30 mg produced greater effects than the 60 mg dose. 4 Only the highest dose of (+/‐)‐glaucine phosphate (60 mg) caused respiratory depression and this was associated with sedation and decreased performance in the digit symbol substitution test. 5 Neither antitussive agent had significant effects upon pulse or blood pressure and codeine phosphate had no detectable sedative activity.