Pharmacokinetics of tiaprofenic acid in children after a single oral dose

Abstract

Twelve healthy children in three age groups anaesthetized for minor surgery were given a single oral dose of tiaprofenic acid (3 mg.kg-1) (TA). Seven blood samples and zero to 8 and 8 to 24 h urines were collected. TA concentrations in plasma and urine were measured by HPLC. No significant difference was found between the age groups in the kinetic parameters of TA and no correlation was found between these parameters and age: tmax = 2.12 h, Cmax = 8.78 mg.l-1, AUC(0----8 h) 33.9 mg.h.l-1, AUC = 39.3 mg.h.l-1, t1/2 = 2.35 h, Vt = 0.319 l.kg-1, CL = 0.094 l.h-1.kg-1. Renal clearance was 14 ml.h-1.kg-1.33% of the TA dose was recovered in the 24 h urine, 48% of which was conjugated, whereas in adults, TA is only found in urine as conjugates. The apparent plasma clearance was significantly higher (56%) than in 12 healthy adults given 1.5 mg.kg-1 TA. Volume of distribution and t1/2 did not significantly differ between children and adults. Since no relationship has been established between plasma TA and either efficacy or toxicity, a different dose regimen cannot be recommended in 3-11 year-old children from that in adults.

Pharmacokinetics of Meloxicam in Patients With Juvenile Rheumatoid Arthritis

“…The increased clearance of meloxicam seen in children compared with adults also merits further attention. Higher rates of clearance in younger children have also been reported for a number of other NSAIDs, including ibuprofen, diclofenac, piroxicam, indomethacin, and tiaprofenic acid, necessitating dose adjustments in some cases 15–20 . All of the children included in this pharmacokinetic evaluation were participating in a 52‐week open‐label study to assess the clinical efficacy and tolerability of an oral meloxicam suspension for the treatment of JRA, results of which have previously been reported 8…”

“…Higher rates of clearance in younger children have also been reported for a number of other NSAIDs, including ibuprofen, diclofenac, piroxicam, indomethacin, and tiaprofenic acid, necessitating dose adjustments in some cases. [15][16][17][18][19][20] All of the children included in this pharmacokinetic evaluation were participating in a 52-week open-label study to assess the clinical efficacy and tolerability of an oral meloxicam suspension for the treatment of JRA, results of which have previously been reported. 8 Selective COX-2 inhibitors such as meloxicam are increasingly used for the treatment of rheumatic diseases in adults due to their proven efficacy and superior GI tolerability compared with traditional nonselective NSAIDs.…”