Comparison of the pharmacokinetics of naproxen tablets and suspension in children.
Twenty-three children, aged 8 to 14 years, with postoperative pain, were randomly assigned to receive a fixed 250-mg dose (4.66-7.58 mg/kg) of naproxen as either a liquid suspension or tablet. After an overnight fast, the serum concentrations were measured before and at 0.5, 1, 2, 3, 4, 8, 12, 18, and 24 hours after administration of naproxen. The concentration versus time data were best fit to a one-compartment open model. The area under the concentration versus time curve, apparent volume of distribution (VDss/F), and elimination parameters (CL/F, Ke, elimination half-life) were similar in children who received suspension or tablets. Although the apparent maximum peak plasma concentration (Cmax) was greater in children who received tablets compared with those who received the suspension, Cmax/area under the curve (AUC), apparent time to maximum peak concentration (tmax), Ka, and estimated time to 10%, 50%, and 90% absorption (T10, T50, T90) were not different. The dose range was relatively narrow; hence, direct relationships between dose and elimination parameters, VDss/F, apparent tmax, Ka, T10, T50 or T90 were not observed. Neither VDss/F or CL/F were age related over the relatively narrow range of ages that were studied. Elimination of naproxen in our patients was more rapid than has previously been reported in children or adults, however. From a practical standpoint, naproxen tablets and suspension seem to be bioequivalent in fasting children ages 8 to 14 years.
Wells
T G
TG
Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock.
Mortensen
M E
ME
Dietrich
A
A
Walson
P D
PD
Blasier
D
D
Kearns
G L
GL
D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D009288:Naproxen / Q000008:administration & dosage / Q000493:pharmacokinetics*; D010149:Postoperative Pain / Q000188:drug therapy / Q000378:metabolism; D013535:Suspensions; D013607:Tablets
D013535:Suspensions; D013607:Tablets; D009288:Naproxen