Effect of Sleeve Gastrectomy on Buprenorphine Pharmacokinetics: A Planned Case Observation

PurposeBariatric surgery may affect the absorption and metabolism of drugs by various mechanisms. We present a planned case observation of a patient treated with sublingual buprenorphine in an opioid maintenance treatment program, and the observed changes in buprenorphine pharmacokinetics following gastric sleeve surgery.MethodsSerial blood samples during a dose interval of 24 hours were obtained approximately 1 year preoperatively as well as 1 week, 1 month and 12 months postoperatively and key pharmacokinetic variables were calculated.FindingsThe systemic exposure of buprenorphine (AUC) was relatively stable from the preoperative sampling to 1 week postoperatively (−6.3%), but declined markedly at 1 month (−43%) and 12 months (−42%) postoperatively. The maximum concentration of buprenorphine almost doubled at 1 week postoperatively before returning to baseline values 1 month and 12 months postoperatively.ImplicationsThis case observation indicates that after sleeve gastrectomy, the systemic exposure of sublingual buprenorphine can decrease. Clinicians should be aware of the possibility of loss of effect and emerging abstinence symptoms following sleeve gastrectomy. We recommend monitoring the patient closely for abstinence symptoms postoperatively and considering measuring serum concentrations of buprenorphine pre- and postoperatively.