A total of 1, 332 adverse events were reported in 8, 960 patients representing 26, 529 treatment years of growth hormone (GH) included in Kabi Pharmacia International Growth Study (KIGS) as of January 1993. Most were concomitant trivial illnesses. Three recurrences occurred in 174 patients (1.7%) with organic growth hormone deficiency (GHD) after leukemia, 18 in 459 patients (3.9 %) with GHD after brain tumors and 19 in 253 (7.5 %) of the original malignancy after craniopharyngioma. At the time of recurrence the patients had been on GH for 2.8-5.2, 0.1-6.1 and 0.2-8.7 years, respectively. De novo leukemia was reported in a 8-year old boy with idiopathic GHD.The annual incidence of insulin dependent diabetes mellitus (IDDM) was 0.08/1, 000 patients and 0.90/1, 000 patients in idiopathic GHD and Turner syndrome, respectively. Five cases of NIDDM were reported in organic GHD post leukemia and CNS tumors. The annual incidence of slipped epiphysis was significantly higher in organic GHD (2.2/1, 000 patients) compared with the reference of normal healthy childhood population (0.10-0.13/1, 000) and idiopathic GHD (0.17/1, 000) and non GHD short children (0.14/1, 000).The incidence of seizures in children with GHD post CNS tumors and incidence of headache in children with GHD after craniopharyngioma was increased compared with idiopathic GHD. The incidence of adverse events in general was lower in idiopathic GHD and short non-GHD children than in organic GHD and Turner syndrome.