Hydroxyurea
Hydroxyurea is an antimetabolite chemotherapy agent used primarily to treat certain cancers, sickle cell disease, and other blood disorders. It works by inhibiting DNA synthesis in rapidly dividing cells, which helps control the proliferation of abnormal cells. This medication requires regular blood monitoring due to its effects on bone marrow and is typically prescribed by specialists in oncology or hematology.
Hydroxyurea is a chemotherapy agent that treats certain cancers and blood disorders by inhibiting DNA synthesis in rapidly dividing cells.
Key facts at a glance
- ATC
- L01XX05
- RxNorm
- 5552
- Generic
- Hydroxyurea
- Class
- atc-l01
- Brands
- Hydrea, Siklos, Droxia, Xromi
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet, solution, capsule
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
first trimesteravoid if possible
avoid use during pregnancy unless benefits outweigh risks; discuss contraception
regular fetal monitoring and ultrasound assessments
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
second trimesteravoid if possible
avoid use unless benefits significantly outweigh risks
regular fetal growth monitoring
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
third trimesteravoid if possible
discontinue before delivery if possible; consider timing of administration
fetal monitoring and assessment of fetal well-being
Use of this medication in this population requires careful consideration of risks and benefits.
lactation
breastfeedingnot applicable
do not breastfeed during treatment and for at least 1 week after last dose
not applicable
Use of this medication in this population requires careful consideration of risks and benefits.
pediatric_age
childrenweight-based dosing required
use under close pediatric supervision; typically 20-30 mg/kg once daily for sickle cell disease
regular CBC monitoring, growth and developmental assessment
Use with caution and monitor for adverse effects.
geriatric
elderlystart at lower end of dosing range
assess renal and hepatic function before initiating; consider comorbidities
regular CBC, renal function and hepatic function monitoring
Use with caution and monitor for adverse effects.
renal_impairment
severereduce dose by 50% in CrCl <60 mL/min
use with caution; monitor renal function regularly; adjust dose based on creatinine clearance
frequent CBC and renal function monitoring
Use with caution and monitor for adverse effects.
hepatic_impairment
moderate to severeconsider dose reduction
use with caution; monitor liver function tests
regular CBC and hepatic function monitoring
Use with caution and monitor for adverse effects.
Statistics and clinical data
Drug class
Hydroxyurea is classified as an antimetabolite and ribonucleotide reductase inhibitor
Primary indications
Main therapeutic uses of Hydroxyurea
Mechanism of action
Primary pharmacological mechanism
FDA approval year
Initial FDA approval for cancer indications
Hydroxyurea is used to treat chronic myelogenous leukemia, squamous cell carcinomas of the head and neck, melanoma, ovarian cancer, and refractory chronic myelogenous leukemia. It is also prescribed for sickle cell disease to reduce painful crises and the need for blood transfusions, as well as for polycythemia vera and essential thrombocythemia.
Hydroxyurea inhibits the enzyme ribonucleotide reductase, which is responsible for converting ribonucleotides to deoxyribonucleotides—the building blocks of DNA. By blocking this conversion, it prevents DNA synthesis and replication in rapidly dividing cells, ultimately suppressing their growth and proliferation.
Hydroxyurea can cause significant bone marrow suppression, requiring regular blood count monitoring. It is teratogenic and contraindicated during pregnancy. Patients should avoid live vaccines while taking this medication. Common side effects include myelosuppression, nausea, and skin changes. Long-term use may increase the risk of secondary malignancies.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 24, 2026. · Read our editorial policy