[Blood levels and therapeutic effectiveness of piroxicam as affected by the time of administration].

The nonsteroidal antirheumatic preparation hydroxy-2-methyl-N-(2-pyridyl)-2H-1.2-benzothiazine-3-carboxamide 1,1-dioxide (piroxicam, Feldene) from the oxicam group is administered as a single dose of 20 mg/d. The question hence arose as to whether the therapeutic efficacy and the blood level curve (steady state) depend on the time of application. The investigation was carried out in 30 patients with arthroses of peripheral joints receiving the daily dose of piroxicam in the morning, at noon or in the evening. The results showed that irrespective of the time of administration the single dose of 20 mg/d led to a steady-state plasma level with the concentration required for efficacy. The result of therapy attained clinically also proved to be independent of the time of administration.