Version July 2025
Baseline testing is required before starting hydroxyurea, and monitoring continues throughout administration, with more frequent monitoring during dose escalation. Monitored laboratory tests include CBC, reticulocyte count, percent Hb F, and creatinine.
Patients with SCD should receive comprehensive care from a clinician with experience managing hemoglobinopathies. The primary clinician may be aware of other aspects of the patient's clinical condition or the patient's or parents/caregivers' values and preferences that could impact decision-making. Refer to UpToDate for further information on SCD management and the use of hydroxyurea in SCD.
CBC: complete blood count; HU: hydroxyurea; SCD: sickle cell disease, which includes all homozygous (Hb SS) or compound heterozygous genotypes.
* Symptomatic disease generally refers to two or more vaso-occlusive events per year (vaso-occlusive pain, dactylitis, acute chest syndrome, priapism).
Different criteria may be needed for some individuals, such as a single clinically significant episode of dactylitis, hepatic sequestration, or splenic sequestration in an infant; chronic pain; severe, symptomatic anemia due to SCD in an adult; or repeated vaso-occlusive events at lower frequency than that used in trials for any age group.
¶ Genotype is usually inferred from hemoglobin analysis rather than DNA testing. Common genotypes are shown.
Δ Features to consider include:
