Time course of gentamicin serum concentration rebound following hemodialysis.

The rebound in gentamicin serum concentration following hemodialysis was studied in six patients with chronic renal failure. The patients were not infected at the time of the study and received a single dose of gentamicin 2 mg/kg before hemodialysis. Serum samples were obtained immediately after dialysis and at 0.5, 1, 2, and 3 hours following hemodialysis. The average increases in gentamicin serum concentrations were 3.6 percent at 0.5 hour, 12.6 percent at 1 hour, and 6.6 percent at 2 hours. An average decline of 4.2 percent occurred at three hours. Only the increase seen at one hour was significantly different from the gentamicin serum concentration immediately following hemodialysis. This rebound was of small magnitude, though, and may not be clinically significant.