PHARMACOKINETICS OF NALOXONE AND NALTREXONE IN THE DOG

  • 1 January 1979
    • journal article
    • research article
    • Vol. 208 (2), 254-256
Abstract
The serum kinetics of 5 mg/kg of i.v. naloxone or naltrexone [narcotic antagonists] were studied in each of 2 groups of 5 dogs; serum samples were obtained from 2 min-2 h after injection. Serum concentrations were determined by radioimmunoassay. Serum levels of naloxone and naltrexone fell rapidly; serum half-life during the elimination phase was 71.2 .+-. 8.9 min (mean .+-. SE) for naloxone and 85.1 .+-. 9.0 min (mean .+-. SE) for naltrexone. Although human and dog kinetics were similar for naloxone, naltrexone was long-acting in man but was quickly dissipated in the dog.