Ocular and auditory toxicity of long-term, high-dose subcutaneous deferoxamine therapy

There have been few reported ocular side effects of parenterally administered deferoxamine when used for the treatment of transfusional iron overload or acute iron poisoning. No auditory side effects have previously been reported. We describe two siblings with beta-thalassemia major who, while receiving daily subcutaneous infusions of deferoxamine, experienced visual loss secondary to optic neuropathy and sensorineural hearing loss. After discontinuation of the drug one sibling showed almost complete reversal of the optic neuropathy, but the other had a permanent unilateral visual loss. Both had a permanent hearing loss but benefited from hearing aids. The mechanism of these complications is presently unknown. Patients receiving deferoxamine should be closely monitored for ocular and auditory side effects. When such effects are detected the drug should be discontinued and the patient observed for improvement. When improvement has stabilized, therapy should be restarted at a reduced dosage.