Pharmacokinetic monitoring of salicylate therapy in children with juvenile rheumatoid arthritis

Lauren M Pachman, Richard Olufs, Josephine A. Procknal, Gerhard Levy*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

24 Scopus citations


Free and total (sum of free and protein bound) salicylate concentrations in serum were determined in 17 children (age: 4–17 years) with definite juvenile rheumatoid arthritis. These measurements were carried out immediately before and 2,4, and 8 hours after the morning dose during a strict 8 hourly aspirin treatment regimen (regular tablets) started 5 days earlier. The ratio of the 0 to 8 hour total salicylate concentrations was 0.95 ± 0.10 (mean ± SD), indicating that steady state had been attained. The ratio of the maximum to minimum concentrations during the dosing interval ranged from 1.05 to 2.26 and decreased with increasing average concentration. The concentration ratio was less than 1.3 at average salicylate concentrations above 20 mg/100 ml. It is concluded that the timing of a blood sample is not critical for monitoring steady state serum salicylate concentrations in the usual therapeutic range if the dosing interval is 8 hours or less. Free salicylate concentrations increased more than proportionately with increasing total concentrations due to the concentration dependent protein binding of the drug in serum.

Original languageEnglish (US)
Pages (from-to)826-831
Number of pages6
JournalArthritis & Rheumatism
Issue number8
StatePublished - Jan 1 1979

ASJC Scopus subject areas

  • Immunology and Allergy
  • Rheumatology
  • Immunology
  • Pharmacology (medical)

Fingerprint Dive into the research topics of 'Pharmacokinetic monitoring of salicylate therapy in children with juvenile rheumatoid arthritis'. Together they form a unique fingerprint.

Cite this