Comparative pharmacokinetic evaluation of compressed naproxen suppositories in humans.

Compressed naproxen (CAS 22204-53-1) suppositories (250 mg) were formulated by dispersing the drug in molten polyethylene glycol 4000 followed by congealing and pulverizing the mass into granules and then compressing into suppositories. Their pharmacokinetic performance was evaluated and compared with that of a standard naproxen tablet in 12 healthy human volunteers. There were no statistically significant (p > 0.05) differences in Cmax, tmax, t1/2, AUC and mean residence time (MRT) observed after oral and rectal administration of tablet and suppository, respectively. The relative rectal bioavailability of naproxen from the compressed suppositories was 96.7 +/- 2.6%. Pharmacokinetics of naproxen after oral and rectal administration was highly comparable.