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Theophylline kinetics in a geriatric group
Author(s) -
Fox Roger W,
Samaan Saber,
Bukantz Samuel C,
Lockey Richard F
Publication year - 1983
Publication title -
clinical pharmacology and therapeutics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.941
H-Index - 188
eISSN - 1532-6535
pISSN - 0009-9236
DOI - 10.1038/clpt.1983.130
Subject(s) - theophylline , kinetics , medicine , group (periodic table) , anesthesia , pediatrics , chemistry , pharmacology , organic chemistry , physics , quantum mechanics
The influence of age, sex, and smoking on theophylline disposition was studied in 38 healthy subjects ranging in age from 26 to 81 yr. There were 8 young (<60 yr) and 30 geriatric (>60 yr) subjects, including 28 men (8 smokers) and 10 women (3 smokers). A crossover experimental design was used. A single dose of theophylline elixir (5 mg/kg lean body weight [LBW]) was given as a reference product to all subjects. One week later a sustained‐release (SR) theophylline tablet (8 and 6 mg/kg LBW) was given to the young and the geriatric subjects. Serum theophylline concentrations were determined by HPLC. Theophylline elimination (t½β) is shorter in the geriatric group (6.93 and 8.14 hr); total body theophylline clearance is greater in the geriatric group (44.39 and 32.97 ml/kg/hr), and the apparent volume of distribution is also greater in the geriatric group (26.29 and 22.97 l). Sex and smoking did not influence any of the parameters studied. In 93% of the geriatric subjects, serum theophylline levels of 8 to 20 μg/ml were reached at steady state with the SR tablet. Theophylline dose reduction based on an arbitrary age limit is not, therefore, invariably indicated. Clinical Pharmacology and Therapeutics (1983) 34, 60–67; doi: 10.1038/clpt.1983.130