Recombinant human growth hormone (rhGH) was instilled intraperitoneally (i.p.) in six children undergoing continuous cycling peritoneal dialysis (CCPD). Immediate absorption was noted with either 0.250 mg/kg, 0.125 mg/kg, or 0.050 mg/kg of rhGH. Peak serum growth hormone (GH) levels occurred 4 and 8 h following i.p. administration, and the serum GH levels had returned to baseline values at 24 h. In one patient, a higher dosage demonstrated adequate absorption, whereas the lower dosage produced a flat absorption curve. These data indicate that daily i.p. administration of rhGH could be utilized in clinical trials directed toward improving the growth velocity of children undergoing CCPD.