The penetration of ceftriaxone into synovial fluid of the inflamed joint.

Fifteen patients with acute exacerbation of rheumatoid arthritis each received a 1 g bolus intravenous injection of ceftriaxone. Serum and synovial fluid was sampled at intervals between 1 h and 24 h later and assayed for ceftriaxone. Synovial fluid leucocyte counts and albumin content were measured concomitantly. Detectable levels of ceftriaxone were found in synovial fluid and serum 24 h after injection. Synovial fluid ceftriaxone concentration ranged between 66% and 100% of the concomitant serum levels. No correlation was observed between synovial fluid ceftriaxone concentration and synovial fluid leucocyte count and albumin concentration.