- What is hydroxyurea, and how does it work (mechanism of action)?
- What are the side effects of hydroxyurea?
- What is the dosage for hydroxyurea?
- Which drugs or supplements interact with hydroxyurea?
- Is hydroxyurea safe to take if I'm pregnant or breastfeeding?
- What else should I know about hydroxyurea?
What is hydroxyurea, and how does it work (mechanism of action)?
Hydroxyurea (Hydrea) is an oral medication used to treat several types of cancers including chronic myelogenous leukemia (CML), acute myelogenous leukemia (AML), head and neck cancer, malignant melanoma, ovarian cancer, and polycythemia vera (a disorder of the bone marrow). The exact mechanism by which hydroxyurea works to treat cancer is not understood. However, it is thought that hydroxyurea causes an immediate inhibition of DNA synthesis by inhibiting an enzyme called ribonucleotide reductase. Interrupting DNA synthesis reduces the growth of cancer cells.
In-addition to treating cancer, Droxia another oral form of hydroxyurea is used in the management of sickle cell disease. The exact mechanism by which hydroxyurea works to treat sickle cell disease is not understood. The FDA approved hydroxyurea in December 1967.
What brand names are available for hydroxyurea?
Is hydroxyurea available as a generic drug?
Do I need a prescription for hydroxyurea?
What are the side effects of hydroxyurea?
Known side effects include:
- bone marrow suppression (drop in white blood cell, red blood cell and platelet counts),
- sores in the mouth,
- skin rash,
- swelling in the hands, feet, legs and face,
- changes in skin pigmentation,
- hair loss,
- painful urination,
- liver problems,
- shortness of breath,
- metabolic disturbances, and
- kidney problems.
What is the dosage for hydroxyurea?
For treating cancer: Dose should be titrated based on individual patient response. Capsules should be swallowed whole. Hydroxyurea capsules should be handled with extreme care and disposed of properly because it causes cell damage.
For the treatment of solid tumors
- Intermittent therapy: 80 mg/kg administered orally as single dose every third day
- Continuous therapy: 20 to 30 mg/kg administered orally as a single daily dose
- Concomitant therapy with irradiation: Cancer of the head and neck, administer 80 mg/kg orally as a single dose every third day
For the treatment of chronic myelocytic leukemia
20 to 30 mg/kg administered orally as a single daily dose is recommended.
As hydroxyurea is mainly eliminated from the body via the kidneys, dose reductions may be necessary in patients with reduced kidney function.
For the treatment of sickle cell disease
Adults: administer 15 mg/kg by mouth once daily. Dose adjustments are made based on patient's blood counts. Patient's blood counts are monitored every two weeks. If the blood counts are in an "acceptable" range, the dose may be increased by 5 mg/kg/day every 12 weeks until a maximum tolerated dose (highest dose that does not produce toxic blood counts) or 35 mg/kg/day is reached.
Latest Cancer News
Daily Health News
Which drugs or supplements interact with hydroxyurea?
Generally, use of live vaccines is contraindicated during treatment with cancer drugs because cancer drugs weaken the immune system. People with weakened immune systems have a decreased response to vaccines.
Hydroxyurea may cause a drop in platelet counts, an important type of blood cells required for forming blood clots. Use of hydroxyurea with anticoagulants, nonsteroidal anti-inflammatory drugs (NSAIDs), antiplatelets, and thrombolytic agents increases the risk of bleeding.
Antineoplastic agents exert their benefits by killing rapidly growing cancer cells. Use of medications that stimulate cell growth is usually not recommended in patients who have been exposed to cytotoxic chemotherapy within 24 hours. Specifically, the manufacturer of pegfilgrastim (Neulasta) recommends that pegfilgrastim should not be administered to patients who have been treated with cytotoxic chemotherapy within the prior 14 days. Also, chemotherapy should not be administered within 24 hours of pegfilgrastim.
Hydroxyurea may increase blood uric acid concentration. Although no specific dose adjustments are necessary with probenecid or sulfinpyrazone (Anturane), hydroxyurea should be used cautiously with uricosuric medications.
Use of hydroxyurea with didanosine (Videx, Videx EC), with or without stavudine (Zerit, Zerit XR), has been associated with an increased incidence of side effects including pancreatitis and peripheral neuropathy (nerve problems). In general, hydroxyurea is not recommended in HIV patients as decreased CD4 counts, decreased viral suppression, and increased risk of side effects has been reported.
Is hydroxyurea safe to take if I'm pregnant or breastfeeding?
Hydroxyurea can cause harm to the unborn baby and therefore, should not be used during pregnancy. Although there are no adequate and well-controlled studies in pregnant women, in animals studies hydroxyurea was found to cause birth defects.
Hydroxyurea is secreted in human milk. Nursing should be stopped due to the potential for serious adverse reactions in the infant.
What else should I know about hydroxyurea?
What preparations of hydroxyurea are available?
- Hydrea: 500 mg capsules. Hydrea is used an antineoplastic agent.
- Droxia: 200 mg, 300 mg, 400 mg capsules. Droxia is used to treat sickle cell disease.
How should I keep hydroxyurea stored?
Capsules should be stored at room temperature between 59 F to 86 F (15 C to 30 C).
Hydroxyurea (Hydrea, Droxia) is a prescription drug used to treat several types of cancer including types of leukemia, head and neck cancer, malignant melanoma, and ovarian cancer; and polycythemia vera. Side effects, drug interactions, warnings, precautions, dosing, storage, pregnancy, and breastfeeding safety information is included.
Multimedia: Slideshows, Images & Quizzes
Ovarian Cancer Symptoms, Signs, Stages
Learn about ovarian cancer symptoms, diagnosis, and treatments. Follow the progression of ovarian cancer stages from stage 1 to...
Ovarian Cancer Quiz: Test Your Medical IQ
How common is ovarian cancer and who is at risk? Take our Ovarian Cancer Quiz to learn the causes, symptoms, and treatment for...
Melanoma (Skin Cancer) Quiz: Symptoms & Signs
What causes skin cancer? Take our Skin Cancer Quiz to learn about the risks, symptoms, causes, and treatments for this common...
Leukemia Quiz: Test Your Medical IQ
What do you know about leukemia? Did you know there are different types? What are the symptoms? Take the Leukemia Quiz and test...
Picture of Skin Cancer
Excessive exposure to sunlight is the main cause of skin cancer. See a picture of Skin Cancer and learn more about the health...
Cancer-Fighting Foods in Pictures: Resveratrol, Green Tea, and More
Experts have praised certain foods for their ability to reduce cancer risks. Learn which foods and eating strategies may help...
Related Disease Conditions
High Red Blood Cell Count (Polycythemia)
Polycythemia (elevated red blood cell count) is a rare blood disease in which the body produces too many red blood cells. Causes of polycythemia are either primary (acquired or genetic mutations) or secondary (diseases, conditions, high altitude).
Cancer is a disease caused by an abnormal growth of cells, also called malignancy. It is a group of 100 different diseases, and is not contagious. Cancer can be treated through chemotherapy, a treatment of drugs that destroy cancer cells.
Sickle Cell Disease (Sickle Cell Anemia)
Sickle cell anemia (sickle cell disease), a blood disease which shortens life expectancy, is caused by an inherited abnormal hemoglobin. Symptoms of sickle cell anemia may include bacterial infections, painful swelling of the hands and feet, fever, leg ulcers, fatigue, anemia, eye damage, and lung and heart injury. Treatment for sickle cell anemia aims to manage and prevent the worst manifestations of the disease and focuses on therapies that block red blood cells from stacking together, which can lead to tissue and organ damage and pain.
Leukemia is a type of cancer of the blood cells in which the growth and development of the blood cells are abnormal. Strictly speaking, leukemia should refer only to cancer of the white blood cells (the leukocytes) but in practice it can apply to malignancy of any cellular element in the blood or bone marrow, as in red cell leukemia (erythroleukemia).
Skin cancers occur when skin cells undergo malignant transformations and grow into tumors. The most common types of skin cancer, basal cell carcinoma and squamous cell carcinoma, are highly curable when they are diagnosed and treated early. Sun exposure, tanning beds, depressed immune system, radiation exposure, and certain viral infections are risk factors for skin cancer. Skin cancers are treated with surgery or radiation. The prognosis of nonmelanoma skin cancers is generally very good.
There are many types of ovarian cancer, epithelial carcinoma is the most common. Women with a family history of ovarian cancer have an increased risk of developing the disease. Some ovarian cancer symptoms include abdominal pain, nausea, diarrhea, constipation, and abnormal vaginal bleeding, however, they usually do not present until the disease has progressed. Early diagnosis is important for successful treatment.
Head and Neck Cancer
Head and neck cancer is cancer of the oral cavity, salivary glands, paranasal sinuses and nasal cavity, pharynx, larynx, or lymph nodes in the upper part of the neck. These cancers account for 3% to 5% of cancers in the U.S. Tobacco and alcohol use are important risk factors. Treatment may involve surgery, radiation therapy, and/or chemotherapy.
Treatment & Diagnosis
Medications & Supplements
Prevention & Wellness
Health Solutions From Our Sponsors
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
FDA Prescribing Information.