Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 1
pubmed:dateCreated
1976-8-23
pubmed:abstractText
The pharmacokinetics of theophylline were examined in a group of nonsmokers and in heavy smokers (1 to 2 packs/day) before and 3 to 4 mo after cessation of cigarette smoking. The half-life of theophylline in smokers averaged 4.3 (SD = 1.4) hr, significantly shorter than the mean value in nonsmokers (7.0, SD =1.7 hr). The apparent volume of distribution of theophylline was somewhat larger in smokers (0.50 +/-0.12 L/kg) than in nonsmokers (0.38 +/-0.04 L/kg). The body clearance of theophylline was appreciably larger and relatively more variable in smokers (100 +/-44 ml/min/1.73 m2) than in nonsmokers (45 +/-13 ml/min/1.73 m2). Serum concentrations of thiocyanate, a biotransformation product of cyanide which is inhaled with smoke, were used to monitor the smoking status of the subjects. The body clearances of theophylline showed a good correlation (r = 0.785, p less than 0.001) with the serum thiocyanate concentrations. Of the 8 smokers, only 4 managed to refrain from smoking for at least 3 mo, and these subjects showed no significant change in theophylline elimination. The increase in theophylline clearance caused by smoking is probably the result of induction of drug-metabolizing enzymes that do not readily normalize after cessation of smoking.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0009-9236
pubmed:author
pubmed:issnType
Print
pubmed:volume
19
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
546-51
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Effect of smoking on theophylline disposition.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.