Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1975-11-8
pubmed:abstractText
The biologic disposition of methadone in acute and during chronic administration was studied in 12 human volunteers. In the acute study a biexponential methadone plasma level decay was observed. The acute primary half-life (t1/2) of 14.3 hr in combination with the acute secondary t1/2 of 54.8 hr were longer than the single exponential chronic t1/2 of 22.2 hr determined in the same subjects. The urinary and fecal excretion of methadone and its mono-N-demethylated metabolite increased from 22.2% in the acute to 62.0% in the chronic phase of the study. The urinary metabolite 1 to methadone ratio tripled from the acute to the chronic phase. The pupillary effects of methadone monitored throughout 24 hr were nearly the same in magnitude in the acute and the chronic studies, whereas the plasma levels increased 3- to 8-fold following chronic methadone administration. These findings suggest that both dispositional and pharmacologic tolerance are involved in the development of tolerance following chronic administration of methadone.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0009-9236
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
180-90
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1975
pubmed:articleTitle
Methadone in man: pharmacokinetic and excretion studies in acute and chronic treatment.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.