How does hydroxyurea work in sickle cell disease?

Hydroxyurea induces fetal hemoglobin (HbF) production by activating gamma-globin gene expression. HbF inhibits HbS polymerization, reducing sickling, vaso-occlusion, hemolysis, and organ damage. The MSH trial showed 44% reduction in pain crises.

How do I escalate to maximum tolerated dose?

Start at 15 mg/kg/day. Check CBC every 4–8 weeks. If no myelosuppression (ANC >2,000, platelets >80,000, Hgb >5.3 g/dL, reticulocytes >80,000 if Hgb <9), escalate by 5 mg/kg/day. MTD: highest dose without toxicity, typically 25–35 mg/kg/day.

What monitoring is required during hydroxyurea therapy?

CBC with differential every 4 weeks during titration, every 8–12 weeks at stable MTD. Renal function (hydroxyurea is renally cleared) and LFTs annually. HbF level every 3–6 months as efficacy marker. Hold for ANC <2,000/µL or platelets <80,000/µL.

Hydroxyurea Starting Dose Calculator for Sickle Cell Disease

Calculates hydroxyurea starting dose for sickle cell disease: 15–20 mg/kg/day orally (round to nearest 500 mg capsule). Escalate by 5 mg/kg/day every 8–12 weeks to maximum tolerated dose (MTD), targeting HbF ≥20% and MCV increase while monitoring CBC for myelosuppression.

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Hydroxyurea Starting Dose Calculator for Sickle Cell Disease

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Frequently Asked Questions

How does hydroxyurea work in sickle cell disease?

How do I escalate to maximum tolerated dose?

What monitoring is required during hydroxyurea therapy?