Limited information is available concerning the use of ganciclovir (GCV) in patients with severe renal impairment. The pharmacokinetics of GCV were studied in a heart transplant recipient requiring hemodialysis. The total body clearance was calculated to be approximately 5% of that previously reported for patients with normal renal function. GCV was removed by hemodialysis; a single 4-h procedure decreased the concentration in plasma by approximately 50%. GCV can be safely administered to patients with renal insufficiency if concentrations in plasma are monitored.