Apparent decrease in population clearance of theophylline: implications for dosage.

M J Asmus; M M Weinberger; G Milavetz; P Marshik; M E Teresi; L Hendeles

doi:10.1016/s0009-9236(97)90043-6

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Apparent decrease in population clearance of theophylline: implications for dosage.

M J Asmus·M M Weinberger·G Milavetz·P Marshik·M E Teresi·L Hendeles

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Abstract

BACKGROUND: Having observed in recent years that the theophylline dose requirements needed to attain peak serum concentrations of 10 to 20 micrograms/ml infrequently reached previously described mean values, we hypothesized that a downward shift in the range of dose requirements had occurred among patients with asthma. STUDY DESIGN: We examined dosage requirements needed to attain peak serum concentrations of 10 to 20 micrograms/ml in all patients with chronic asthma treated with theophylline by the Pediatric Allergy and Pulmonary Clinic at the University of Iowa from 1990 to 1994 (n = 300) and at the Pediatric Pulmonary Clinic at the University of Florida from 1992 to 1995 (n = 93). We then compared these doses to previous dose requirements from 1978 to 1983 determined in the same manner. RESULTS: Despite similar mean peak serum concentrations during both time periods (14 micrograms/ml), mean theophylline dosage requirements during the period of this study were approximately 25% lower among all age groups than those previously observed (p < 0.001). There were no significant differences in mean dosage requirements between the Iowa and Florida patients in any age group examined. CONCLUSIONS: Theophylline dose requirements needed to attain serum concentrations of 10 to 20 micrograms/ml have decreased significantly from those on which current dosing recommendations are based. This suggests a decrease in mean clearance of the population.

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Adolescent Age Factors Asthma Body Weight Bronchodilator Agents Child Child, Preschool Chronic Disease Drug Administration Schedule Humans Infant Theophylline Comparative Study Journal Article

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M J Asmus, M M Weinberger, G Milavetz, P Marshik, M E Teresi, L Hendeles. 1997. Apparent decrease in population clearance of theophylline: implications for dosage.. https://doi.org/10.1016/s0009-9236(97)90043-6

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