Meloxicam (CAS 71125-38-7, UH-AC 62 XX) is a new non-steroidal anti-inflammatory drug (NSAID) which was developed for the treatment of osteoarthritis and rheumatoid arthritis. The basic clinical pharmacokinetics of meloxicam (7.5-30 mg) have been investigated in 78 healthy male volunteers after single and multiple dosing via oral, intravenous and rectal routes. Plasma concentrations of meloxicam were determined by validated high performance liquid chromatography (HPLC) methods. The pharmaco-kinetic profile of meloxicam is characterized by almost complete absorption over a prolonged phase-avoiding high initial drug concentrations- and is bound to plasma proteins by more than 99.5%. Meloxicam is metabolized to four biologically inactive metabolites and excreted in urine and faeces with an elimination half-life (t1/2) of around 20 h. This is reflected in a total plasma clearance of 7 to 8 ml/min. Steady state is achieved within 3 to 5 days. In addition, the pharmacokinetic parameters are linear over the entire dose range, there are no changes with multiple dosing and bioequivalence was shown for a number of different formulations. The results indicate that meloxicam is suitable for once-daily administration and that a switch from one formulation to another is easily possible if necessary or convenient for the patient.