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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5 Pt 1
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pubmed:dateCreated |
1976-8-23
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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.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
May
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pubmed:issn |
0009-9236
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
19
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
546-51
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:1277710-Adult,
pubmed-meshheading:1277710-Female,
pubmed-meshheading:1277710-Half-Life,
pubmed-meshheading:1277710-Humans,
pubmed-meshheading:1277710-Kinetics,
pubmed-meshheading:1277710-Male,
pubmed-meshheading:1277710-Saliva,
pubmed-meshheading:1277710-Smoking,
pubmed-meshheading:1277710-Theophylline,
pubmed-meshheading:1277710-Thiocyanates
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pubmed:year |
1976
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pubmed:articleTitle |
Effect of smoking on theophylline disposition.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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