The effectiveness of desferrioxamine (DFO) in ameliorating the severity of the acute haemolysis of glucose-6-phosphate dehydrogenase (G6PD) deficiency was studied in 167 children with G6PD deficiency during an acute haemolytic crisis. All patients received packed cell transfusion on admission if their Hb levels were <8 g/dl, which was repeated as needed. Eighty patients also received a single dose of DFO 30-40 mg/kg by slow intravenous infusion (DFO group). The remaining 87 children did not receive DFO (control group). The need for more than one transfusion was less frequent in the DFO group as compared to the control group (p = 0. 01). The need for late transfusion (transfusion after 36 h of admission) was also less in the DFO group (7%) compared to 21% in the control group (p = 0.02). On average, children in the DFO group needed less packed red blood cells (16.5 ml/kg body weight) than the control group (22.8 ml/kg body weight) and the difference was highly significant (p = 0.0001). We conclude from this study that DFO in a small dose is effective in the treatment of acute haemolytic crises of G6PD deficiency. It shortens the duration of the crisis and decreases the amount of blood transfusion needed.