February 1981

Monitoring Children on Sustained-Release Therapy by Salivary Theophylline Levels

Author Affiliations

From the College of Pharmacy (Drs Kelly and Hadley) and the Departments of Pediatrics (Dr Murphy) and Family, Community, and Emergency Medicine (Dr Skipper), School of Medicine, University of New Mexico Pediatric Pulmonary Center, Albuquerque.

Am J Dis Child. 1981;135(2):137-139. doi:10.1001/archpedi.1981.02130260029009

• The serum-saliva theophylline level ratio was measured in 19 chronically asthmatic children after their conditions were stabilized on a sustained-release theophylline preparation. Simultaneous serum and saliva samples were collected at 0, 4, 6, and 10 hours after theophylline dose and measured by high-pressure liquid chromatography. The mean ratio for the group of 1.52 ± 0.64 approximated the mean ratio from previous reports. However, the correlation coefficient (r =.80) was lower, and the interpatient and intra-patient variability (25% and 23%) much higher, than in previous reports. The possible mechanism of these findings in relation to sustained-release preparations are discussed. These data question the use of salivary theophylline determinations to monitor therapy. Dosage should be based on serum measurements.

(Am J Dis Child 1981;135:137-139)