Description and Brand Names

Drug information provided by: Micromedex

US Brand Name

  1. Droxia
  2. Hydrea


Hydroxyurea is used to treat cancer of the white blood cells called chronic myeloid leukemia (CML). It may also be given together with radiation treatment for head and neck cancer (advanced squamous cell cancer). Hydroxyurea interferes with the growth of cancer cells, which are eventually destroyed by the body.

Hydroxyurea is used in adult patients with sickle cell anemia to prevent painful episodes and reduce the need for blood transfusions. It works by making the red blood cells more flexible.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

  • Capsule
  • Tablet

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies have not been performed on the relationship of age to the effects of hydroxyurea in the pediatric population. Safety and efficacy have not been established.


Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of hydroxyurea in the elderly. However, elderly patients are more likely to have age-related kidney problems, which may require caution and an adjustment in the dose for patients receiving hydroxyurea.


Information about this hydroxyurea-oral-route
Pregnancy Category Explanation
All Trimesters D Studies in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy in a life threatening situation or a serious disease, may outweigh the potential risk.


There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

  • Rotavirus Vaccine, Live

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Adenovirus Vaccine Type 4, Live
  • Adenovirus Vaccine Type 7, Live
  • Bacillus of Calmette and Guerin Vaccine, Live
  • Didanosine
  • Influenza Virus Vaccine, Live
  • Measles Virus Vaccine, Live
  • Mumps Virus Vaccine, Live
  • Poliovirus Vaccine, Live
  • Rubella Virus Vaccine, Live
  • Smallpox Vaccine
  • Stavudine
  • Typhoid Vaccine
  • Varicella Virus Vaccine
  • Yellow Fever Vaccine

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Anemia (low red blood cells) or
  • Bone marrow problems or
  • Leukopenia (low white blood cells) or
  • Thrombocytopenia (low blood platelet levels)—Use with caution. May make these conditions worse.
  • Kidney disease—Use with caution. The effects may be increased because of slower removal of the medicine from the body.

Proper Use

Use this medicine exactly as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered.

This medicine comes with a patient information insert. Read and follow the instructions carefully. Ask your doctor if you have any questions.

Your doctor may want you to take folic acid with this medicine.

Hydroxyurea should be handled with care. People who are not taking this medicine should avoid touching it. To decrease your chance of touching the medicine:

  • Wear disposable gloves when handling the bottle or capsules.
  • Wash your hands with soap and water before and after contact with the bottle or capsules.
  • Do not open the capsules. Avoid exposure to crushed or opened capsules.
  • If you touch an opened or crushed capsule, wash your skin right away with soap and water.
  • If powder from the capsule gets into your eyes, rinse them with water or an isotonic eyewash for 15 minutes.
  • If powder from the capsule is spilled, wipe it up right away with a damp disposable towel. Place the towel and the empty capsule in a closed container, such as a plastic bag.
  • The area where the powder spilled should be cleaned 3 times using a detergent solution followed by clean water.


The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (capsules):
    • For cancer of the head and neck:
      • Adults—Dose is based on body weight and must be determined by your doctor. The dose is 15 milligrams (mg) per kilogram (kg) of body weight per day, taken as a single dose. Your doctor may adjust your dose as needed.
      • Children—Use and dose must be determined by your doctor.
    • For chronic myelocytic leukemia (CML):
      • Adults—Dose is based on body weight and must be determined by your doctor. The dose is 15 milligrams (mg) per kilogram (kg) of body weight per day, taken as a single dose. Your doctor may adjust your dose as needed.
      • Children—Use and dose must be determined by your doctor.
    • For sickle cell anemia:
      • Adults—Dose is based on body weight and must be determined by your doctor. At first, the dose is 15 milligrams (mg) per kilogram (kg) of body weight per day, taken as a single dose. Your doctor may adjust your dose as needed. However, the dose is usually not more than 35 mg per kg of body weight per day.
      • Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.


Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.


It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Women should use an effective form of birth control during treatment and for at least 30 days after the last dose. Men should use an effective form of birth control during treatment and for at least 1 year after the last dose to prevent pregnancy in a sexual partner. If a pregnancy occurs while using the medicine, tell your doctor right away.

Hydroxyurea can temporarily lower the number of white blood cells in your blood which increases the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

  • If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
  • Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
  • Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
  • Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
  • Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
  • Avoid contact sports or other situations where bruising or injury could occur.

Using this medicine for a long time may increase your risk of developing leukemia (cancer of the blood) or skin cancer. Use a sunscreen and protective clothing to protect your skin. Talk to your doctor if you have concerns about this risk.

If you had radiation treatment in the past, this medicine might cause your skin to become very red when you have radiation again. Tell your doctor right away if you have darkening or redness of the skin.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

  1. Cough or hoarseness
  2. fever or chills
  3. lower back or side pain
  4. painful or difficult urination

Less common

  1. Black, tarry stools
  2. blackening of the fingernails and toenails
  3. blood in the urine or stools
  4. pinpoint red spots on the skin
  5. sores in the mouth and on the lips
  6. unusual bleeding or bruising


  1. Confusion
  2. convulsions (seizures)
  3. difficulty with urination
  4. dizziness
  5. headache
  6. joint pain
  7. seeing, hearing, or feeling things that are not there
  8. swelling of the feet or lower legs

Incidence not known

  1. Bleeding under the skin
  2. blisters on the skin
  3. bluish or pale color on the skin of the fingers or toes
  4. coldness of the fingers or toes
  5. crater-like lesions on the skin
  6. itching skin
  7. numbness or tingling of the fingers or toes
  8. pain in the fingers or toes
  9. unusual tiredness or weakness
  10. weight loss

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Diarrhea
  2. drowsiness
  3. loss of appetite
  4. nausea or vomiting

Less common

  1. Constipation
  2. redness of skin at the place of radiation
  3. skin rash and itching

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.