This is a phase III, randomized, double-blind, placebo-controlled clinical trial with sickle cell disease patients older than 1 year of age. The patients were randomly assigned to take 0.1 g/kg/day of either L-arginine or placebo orally. Adverse events were monitored by a safety committee. The variables were assessed while patients were in remission, as part of their routine care: weight, blood pressure, full blood cell count, creatinine and dosage of methemoglobin at baseline and at each follow-up visit. Peripheral oxygen saturation (SpO2), fetal hemoglobin, lactate dehydrogenase and tricuspid regurgitant jet velocity were measured through transthoracic Doppler echocardiogram before and after treatment.
