PURPOSE: To describe a case of breakthrough pain associated with a reduction in serum buprenorphine concentration during dialysis.
METHODS: Pharmacokinetic sampling of total and free buprenorphine and norbuprenorphine in an 80 year old male undergoing haemodialysis three times per week who received 5760 µg oral and transdermal buprenorphine daily was performed. The patient's serum albumin concentration was 23g/l (reference range: 35-52 g/l).
FINDINGS: Pharmacokinetic sampling revealed a free buprenorphine fraction of 32% (consistent with the hypoalbuminaemia), which was markedly reduced at the end of dialysis (free buprenorphine concentration 2.4 µg/l before vs. <0.1 µg/l after dialysis).
IMPLICATIONS: Clinicians should be aware that some patients may require extra buprenorphine doses during dialysis to prevent significant falls in the concentration of active drug.