Treatment of secondary haemosiderosis with desferrioxamine (DFO) was evaluated in children and adolescents treated by chronic haemodialysis. Ten patients were treated with intravenous DFO (25 mg/kg body weight). Three patients received DFO throughout dialysis, four were treated only during the last hour of each dialysis session, and three other patients were successively treated with DFO according to both regimens. A significant decrease and normalisation of serum ferritin was achieved only with DFO administered during the last hour of dialysis. In some patients blood haemoglobin (Hb) increased during treatment. Although serum ferritin levels remained normal, Hb levels returned to pretreatment values following discontinuation of DFO treatment. Visual and auditory neurotoxicity was not noticed but increased systemic infections were observed.