OBJECTIVE Chelation therapy is often necessary for patients who undergo chronic transfusion therapy for myelodysplastic syndromes. In these patients, deferoxamine, the most widely used chelating agent, has been reported to be effective in reducing the iron burden and the transfusion requirement. Unfortunately, compliance with the drug, that is usually administered by slow subcutaneous infusion via a battery operated pump, is often poor, especially in elderly patients. METHODS To verify efficacy and tolerability of deferoxamine by subcutaneous bolus injection as compared to the conventional pump-driven slow infusion, eleven patients affected by oncohematologic diseases were given 2 g of deferoxamine diluted in 10 mL of distilled water over twelve hours by continuous infusion, or by bolus injection in two divided doses. RESULTS Mean urinary excretion was comparable with the two methods, being 9,183 +/- 4,349 micrograms/48 h after two daily subcutaneous bolus injections and 8,291 +/- 3,970 micrograms/48 h with the slow infusion. The bolus injection was preferred by all eleven patients, who chose to continue chelation therapy by this method. CONCLUSIONS The iron excretion induced by bolus injection is not statistically different from that induced by subcutaneous infusion. The side effects are acceptable. Subcutaneous bolus injection of deferoxamine is an acceptable alternative to slow, pump-driven infusion.