Adverse effects of hydroxyurea in beta-thalassemia intermedia patients: 10 years' experience.

The aim of this study was to evaluate the tolerance and adverse effects of hydroxyurea (HU) in thalassemia intermedia (TI) patients who had been treated by HU for a period of 10 years. One hundred forty-three TI patients, including 78 male and 65 female, median age 21 years old (range: 5-37 years old), who were treated by HU were investigated as a case study, and 106 TI, including 63 male and 43 female, median age 22 years old (range: 5-39 years old), who were not treated by any HU as a control group. Mean dose of HU treatment was 10.74 mg/kg/day (range: 8-12 mg/kg/day) and adverse effects of HU were recorded in 44 (30.7%) patients. Dermatologic side effects were most commonly seen, followed by neurological and gastrointestinal adverse effects. There were not any reports of hematologic toxicity or any signs of bone marrow suppression during HU treatment. Statistical analysis showed a positive correlation between advancing age and the presence of adverse effects during HU treatment (P < .001). But there were not any significant relations among gender, HU dose, and duration of HU treatment and the presence of adverse effects (P > .05). It was also observed that splenectomized patients more frequently experienced adverse effects of HU (P < .05). According to these results, it seems that most of adverse effects in low-dose HU therapy in patients with TI, at least in short and medium terms, are minor and can be tolerated without needs of discontinuation of treatment.