Disposition of Morphine in Man

Science  22 Oct 1971:
Vol. 174, Issue 4007, pp. 421-422
DOI: 10.1126/science.174.4007.421


The disposition of morphine was investigated by means of radioimmunoassay after a single intravenous dose (10 milligrams per 70 kilograms) was administered to 10 adult normal male subjects who had not received other drugs for 2 weeks preceding the study. A multiphasic decline in serum concentrations of morphine occurred. Detectable blood concentrations of morphine, or of a metabolite, or of both persisted for 48 hours after a single intravenous dose.