Integrated plasma and synovial fluid pharmacokinetics of tenoxicam in patients with rheumatoid arthritis and osteoarthritis: factors determining the synovial fluid/plasma distribution ratio.

Single oral doses of 40 mg of the nonsteroidal antiinflammatory drug, tenoxicam, were given to four patients (three with rheumatoid arthritis, one with osteoarthritis). The concentrations of the drug in synovial fluid and plasma were measured by a specific high-performance liquid chromatography meth