Recombinant human growth hormone (rhGH) has become available for treatment of growth failure in uremic children. Since GH raises the glomerular filtration rate (GFR) in healthy individuals, there has been concern that treatment with rhGH, by its action on glomerular hemodynamics, may adversely affect the progression of renal failure. To further address this issue, inulin clearance (enzymatic steady-state infusion technique) was measured in 7 healthy normotensive adult volunteers and 7 patients with chronic renal failure from glomerular or non-glomerular causes. Subjects were given 4.5 U bid of rhGH by s.c. injection for 3 days. In volunteers, a significant increase in Cin was noted 72 h after start of rhGH administration from 120 ml/min/1.73 m2 (range 91-158) to 133 (108-167) (p less than 0.02). In contrast, no significant increase in Cin was noted in patients with chronic renal failure (baseline Cin 21 ml/min/1.73 m2, 15-32; after rhGH 22 ml/min/1.73 m2, 15-32) despite pronounced effects of GH on S-cholesterol and urea excretion rate. The results show that stimulation of GFR by short-term administration of rhGH is obliterated in chronic renal failure.