Hydrea is a brand-name prescription medication. It’s FDA-approved to treat certain types of the following cancers in adults:
- Chronic myeloid leukemia. This is a type of blood cancer. For this use, the chronic myeloid leukemia must be resistant. The term “resistant” means the cancer hasn’t gotten better after you used other treatments in the past.
- Skin cancer of the head and neck. Hydrea is used to treat a type of skin cancer called squamous cell carcinoma. For this use, the cancer must affect the head or neck, but not the lips. The cancer must also be locally advanced, which means it spread to areas of the body near where it started. For this condition, Hydrea is prescribed in combination with chemotherapy and radiation therapy.
For more information, see the “Hydrea uses” section below.
Hydrea contains the active drug hydroxyurea and belongs to a class of cancer drugs called antimetabolites.
Hydrea comes as an oral capsule. It’s available in one strength: 500 milligrams (mg).
For information about the effectiveness of Hydrea, see the “Hydrea uses” section below.
Hydrea is a brand-name drug that contains the active drug hydroxyurea. This active drug is also available as a generic medication. So the generic name for Hydrea is hydroxyurea. A generic drug is an exact copy of the active drug in a brand-name medication.
The generic is considered to be as safe and effective as the original drug. Generics tend to cost less than brand-name drugs.
If you’re interested in taking the generic form of Hydrea, talk with your doctor. They can tell you if it comes in forms and strengths that can be used for your condition.
Hydrea can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Hydrea. These lists do not include all possible side effects.
Hydrea comes in one strength: 500 milligrams (mg). These side effects are regarding this 500-mg strength.
For more information about the possible side effects of Hydrea, talk with your doctor or pharmacist. They can give you tips on how to manage any side effects that may be concerning or bothersome.
Note: The Food and Drug Administration (FDA) tracks side effects of drugs it has approved. If you would like to notify the FDA about a side effect you’ve had with Hydrea, you can do so through MedWatch.
Mild side effects
Mild side effects* of Hydrea can include:
- macrocytosis (a condition that occurs when red blood cells are larger than usual)
- digestive problems†
- loss of appetite†
Most of these side effects may go away within a few days or a couple of weeks. However, if they become more severe or don’t go away, talk with your doctor or pharmacist.
* This is a partial list of mild side effects from Hydrea. To learn about other mild side effects, talk with your doctor or pharmacist, or view Hydrea’s prescribing information.
† For more information about this side effect, see “Side effect details” below.
Serious side effects
Serious side effects from Hydrea aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.
Serious side effects and their symptoms can include:
- Cancers, such as other forms of leukemia and skin cancer. Depending on the specific type of cancer, symptoms can include:
- skin sores that bleed or don’t heal
- Severe skin ulcers (sores). Symptoms around the affected area can include:
- pain, swelling, or tenderness
- scabbing or flaking
- redness or discoloration
- Severe lung problems, such as pulmonary fibrosis (lung scarring) and pneumonitis (swelling of the air sacs in the lungs). Symptoms can include:
- Low blood cell counts.*
- Allergic reaction.*
* For more information about this side effect, see “Side effect details” below.
Side effect details
Here’s some detail on certain side effects this drug may cause.
Low blood cell counts
Hydrea may decrease the activity of bone marrow, which can lead to low blood cell counts. (Bone marrow is the spongy material inside of bones.) However, it’s not known how often this side effect was reported in clinical trials of Hydrea.
Hydrea may cause a low level of the following blood cells:
- Platelets, which are a type of red blood cell that helps your blood clot. A low level of platelets is called thrombocytopenia. Symptoms include bleeding or bruising more easily than usual.
- Leukocytes, which are a type of white blood cell. A low level of leukocytes is called leukopenia. Symptoms can include fever, sweating, and chills.
- Red blood cells. A low level of red blood cells can lead to anemia. Symptoms can include fatigue and paleness or skin appearing lighter than usual. Hydrea can cause a type of anemia called hemolytic anemia. This is a condition in which your red blood cells are destroyed faster than your body can replace them. In addition to the symptoms above, hemolytic anemia can cause dark urine or jaundice.
Your doctor will likely check your levels of platelets, red blood cells, and white blood cells before you start Hydrea treatment. They’ll also check your levels from time to time while you take the drug.
If you have symptoms of low blood cell counts while taking Hydrea, talk with your doctor. They may treat you to increase your blood cell counts. Your doctor may also adjust your Hydrea dosage or prescribe a drug other than Hydrea.
Digestive problems are possible with Hydrea. These side effects weren’t reported in clinical trials of the drug. However, digestive problems have been commonly reported with Hydrea since the drug became available for use.
Digestive problems that can occur with Hydrea include:
To stay hydrated while taking Hydrea, you can drink water or sports drinks, such as Gatorade.
If you have digestive problems while taking Hydrea, talk with your doctor. They can suggest ways to help ease your symptoms. For example, your doctor may recommend you take Hydrea with food to help prevent digestive problems.
Loss of appetite
Loss of appetite is a more common side effect of Hydrea. This wasn’t reported in clinical trials of the drug. However, loss of appetite has been commonly reported since Hydrea became available for use.
Loss of appetite may be caused by digestive problems, which is another possible side effect of Hydrea. For details, see “Digestive problems” above.
If you have loss of appetite with Hydrea, talk with your doctor. Instead of eating larger meals, it may be helpful to eat several small meals and snacks throughout the day. And be sure to stay hydrated, even if you aren’t able to eat as much as usual.
As with most drugs, some people can have an allergic reaction after taking Hydrea. This side effect wasn’t reported in clinical trials of the drug. However, it has been reported since Hydrea became available for the public to use.
Symptoms of a mild allergic reaction can include:
A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:
- swelling under your skin, typically in your eyelids, lips, hands, or feet
- swelling of your tongue, mouth, or throat
- trouble breathing
Call your doctor right away if you have an allergic reaction to Hydrea, as the reaction could become severe. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.
What happens with cancer
Typically, cells in the body stop multiplying and die when they’re no longer needed. However, with cancer, cells continue to grow, divide, and spread. This happens even when the body doesn’t need these cells.
Hydrea’s mechanism of action
Hydrea’s mechanism of action* isn’t completely understood. The drug is thought to work by blocking enzymes (proteins) that help cancer cells grow.
* “Mechanism of action” is the way a drug works in the body.
How long does it take to work?
Hydrea starts working right away to treat cancer. However, it may take several weeks for your cancer to stop growing.
You likely won’t notice Hydrea working in your body. Your doctor will order tests during your treatment to check if the drug is working for you.
The Food and Drug Administration (FDA) approves prescription drugs such as Hydrea to treat certain conditions. Hydrea may also be prescribed off-label for other conditions. Off-label drug use means prescribing a drug for a purpose other than what it’s been approved for by the FDA.
Here’s some information about Hydrea’s uses and the medication’s effectiveness.
Hydrea for chronic myeloid leukemia
Hydrea is FDA-approved to treat a certain type of chronic myeloid leukemia (CML) in adults. To be specific, Hydrea is used to treat resistant CML. This means the CML did not get better after you used other treatments in the past.
Symptoms of CML can include:
You can learn more about CML by visiting our cancer hub.
Effectiveness for chronic myeloid leukemia
Hydra is FDA-approved to treat resistant CML. This approval means that it has been found effective at treating this type of cancer. If you have additional questions about the effectiveness of Hydrea, talk with your doctor. They can also advise you on whether Hydrea would be an effective treatment option for you.
Hydrea for skin cancer of the head and neck
Hydrea is FDA-approved to treat a type of skin cancer called squamous cell carcinoma (SCC) in adults. For this use, the cancer must affect the head or neck. The cancer must also be locally advanced, which means it has spread to areas of the body near where it started. In this case, the cancer has spread to tissues or lymph nodes near the head and neck.
Hydrea is not approved to treat SCC of the lips.
Symptoms of SCC on the skin can include a:
- patch that feels rough
- wart-like growth
- darkened or discolored area that may resemble an age spot
- little growth that looks like the horn of a rhinoceros
In lighter skin tones, SCC often forms on skin that’s exposed to the sun, such as the face, ears, or neck. In deeper skin tones, the cancer often appears on skin that isn’t exposed to the sun, such as the feet or legs.
To learn more about skin cancer, visit our cancer hub.
Effectiveness for skin cancer of the head and neck
Hydra is FDA-approved to treat SCC of the head and neck. This approval means that it has been found effective at treating this type of cancer. If you have additional questions about the effectiveness of Hydrea, talk with your doctor. They can also advise you on whether Hydrea would be an effective treatment option for you.
Hydrea and children
Hydrea is not approved for use in children. Clinical trials of Hydrea included only adults. So it isn’t known if Hydrea is safe or effective for children.
For treating skin cancer, Hydrea is prescribed in combination with chemotherapy and radiation therapy. This is also known as chemoradiation, and it’s a type of cancer treatment that uses radiation to kill cancer cells.
Your doctor may prescribe Hydrea with other cancer drugs. Your specific treatment regimen will depend on the type and severity of your cancer and how well the treatment works.
Your doctor may also prescribe folic acid in combination with Hydrea. Taking folic acid can help lower your risk of macrocytosis. (This is a condition that occurs when your red blood cells are larger than usual.)
If you have questions about taking Hydrea with other therapies, talk with your doctor.
Here are answers to some frequently asked questions about Hydrea.
Is Hydrea approved to treat other blood conditions, such as sickle cell disease or polycythemia vera?
However, other forms of hydroxyurea (the active drug in Hydrea) are approved to treat sickle cell disease. This includes the brand-name drugs Droxia and Siklos. Both Hydrea and Droxia come as oral capsules, while Siklos comes as an oral tablet. Each form of hydroxyurea comes in a different strength.
In addition, Hydrea may be prescribed off-label to treat polycythemia vera. Off-label drug use means prescribing a drug for a purpose other than what it’s been approved for by the FDA.
If you have questions about taking Hydrea to treat other blood conditions, talk with your doctor. They can recommend the best treatment for you.
My platelet level is high. Can I take Hydrea for thrombocytosis?
Hydrea is not currently approved to treat thrombocytosis, which is a high level of platelets. (Platelets are a type of red blood cell that help your blood clot.) However, Hydrea may be prescribed off-label for this purpose. Off-label drug use means prescribing a drug for a purpose other than what it’s been approved for by the FDA.
Hydrea can cause a low platelet level as a side effect. So the drug may be effective for lowering a high platelet level.
If you have a high platelet level, talk with your doctor. They can advise you on whether Hydrea may be used for your condition. Or they may recommend a different treatment option.
Is Hydrea a blood thinner?
No, Hydrea is not a blood thinner. Blood thinners are medications used to treat and help prevent blood clots.
Hydrea is a type of cancer treatment called an antimetabolite. Hydrea is approved to treat certain forms of chronic myeloid leukemia and skin cancer. (For details, see the “Hydrea uses” section above.)
Keep in mind that Hydrea can cause a low platelet level as a side effect. (Platelets are a type of red blood cell that helps your blood clot.) So if your level of platelet is low, you may have a decreased risk of blood clots. However, Hydrea is not specifically used for this purpose.
If you have questions about Hydrea’s uses, talk with your doctor or pharmacist.
Does Hydrea cause hair loss?
If you have bothersome hair loss with Hydrea, talk with your doctor. They can suggest ways to ease your symptoms.
Are skin reactions, such as rash, side effects of Hydrea?
Certain skin reactions are possible with Hydrea. It’s not known for sure if these side effects occurred in clinical trials of the drug. However, various skin reactions have been reported since Hydrea became available for use.
Examples of skin reactions that can happen with Hydrea include:
- redness or discoloration in the face, arms, or legs
- darkened skin or nails
- severe skin ulcers (sores)
- radiation dermatitis (damage to the outer layer of skin caused by radiation therapy)
If you have a rash or other skin reactions with Hydrea, be sure to tell your doctor. Keep in mind that rash can be a symptom of allergic reaction,* which can be severe for some people. Your doctor will likely check for other symptoms of allergic reaction with Hydrea.
* To learn more, see the “Hydrea side effects” section above.
The Hydrea dosage your doctor prescribes will depend on several factors. These include:
- the type and severity of the condition you’re taking Hydrea to treat
- your age
- the side effects you experience
- other medical conditions you may have, including your kidney function
The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.
Drug forms and strengths
Hydrea comes as an oral capsule. It’s available in one strength of 500 milligrams (mg).
Dosage for chronic myeloid leukemia
Hydrea is approved to treat a certain type of chronic myeloid leukemia (CML) in adults.
The manufacturer of Hydrea hasn’t provided specific dosage recommendations for CML. Your exact dosage of Hydrea will depend on your body weight, the severity of your condition, and whether you have kidney disease. It will also depend on whether you’re an older adult, as this age group typically requires a lower dose than usual. Your doctor will instruct you on the exact dosage of Hydrea to take.
Dosage for skin cancer of the head and neck
The manufacturer of Hydrea hasn’t provided specific dosage recommendations for SCC. Your exact dosage of Hydrea will depend on your body weight, the severity of your condition, and whether you have kidney disease. It will also depend on whether you’re an older adult, as this age group typically requires a lower dose than usual. Your doctor will advise you on the exact dosage of Hydrea to take.
What if I miss a dose?
The manufacturer of Hydrea hasn’t provided recommendations for a missed dose. If you miss a dose of Hydrea, talk with your doctor or pharmacist. They can recommend whether you’ll take the missed dose of Hydrea or skip it.
To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.
Will I need to take this drug long term?
Hydrea is meant to be used as a long-term treatment. If you and your doctor determine that Hydrea is safe and effective for you, you’ll likely take it long term.
As with all medications, the cost of Hydrea can vary. To find current prices for Hydrea capsules in your area, check out GoodRx.com.
The cost you find on GoodRx.com is what you may pay without insurance. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.
Keep in mind that you may be able to get a 90-day supply of Hydrea. If approved by your insurance company, getting a 90-day supply of the drug could reduce your number of trips to the pharmacy and help lower the cost. If you’re interested in this option, check with your doctor, pharmacist, or insurance company.
Before approving coverage for Hydrea, your insurance company may require you to get prior authorization. This means that your doctor and insurance company will need to communicate about your prescription before the insurance company will cover the drug. The insurance company will review the prior authorization request and decide if the drug will be covered.
If you’re not sure if you’ll need to get prior authorization for Hydrea, contact your insurance company.
Financial assistance to help you pay for Hydrea may be available.
Medicine Assistance Tool and NeedyMeds are two websites offering resources that may help decrease the price you pay for Hydrea. They also offer tools to help you find low-cost healthcare, as well as educational resources. To find out more, visit their sites.
To learn more about saving money on prescriptions, check out this article.
Hydrea may be available through a mail-order pharmacy. Using this service may help lower the drug’s cost and allow you to get your medication without leaving home.
If recommended by your doctor, you may be able to receive a 90-day supply of Hydrea, so there’s less concern about running out of the medication. If you’re interested in this option, check with your doctor, pharmacist, or insurance company. Some Medicare plans may help cover the cost of mail-order medications.
If you don’t have insurance, you can ask your doctor or pharmacist about online pharmacy options.
Hydrea is available in a generic form called hydroxyurea. A generic drug is an exact copy of the active drug in a brand-name medication. The generic is considered to be as safe and effective as the original drug. And generics tend to cost less than brand-name drugs. To find out how the cost of hydroxyurea compares with the cost of Hydrea, visit GoodRx.com.
If your doctor has prescribed Hydrea and you’re interested in taking hydroxyurea instead, talk with your doctor. They may prefer one version or the other. You’ll also need to check your insurance plan, as it may only cover one or the other.
There aren’t any known issues with drinking alcohol while taking Hydrea.
However, if you consume alcohol, it’s best to talk with your doctor about the amount that’s safe for you to drink during Hydrea treatment.
Hydrea can interact with several other medications. Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase side effects or make them more severe.
Hydrea and other medications
Below are some medications that can interact with Hydrea. This section does not contain all drugs that may interact with Hydrea.
Before taking Hydrea, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also, tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.
Types of drugs that can interact with Hydrea include antiretroviral drugs (such as efavirenz and zidovudine), which are used to treat HIV. Taking Hydrea with these drugs can cause certain side effects, such as:
If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.
Hydrea and herbs and supplements
There aren’t any herbs or supplements that have been specifically reported to interact with Hydrea. However, you should still check with your doctor or pharmacist before using any of these products while taking Hydrea.
Hydrea and foods
There aren’t any foods that have been specifically reported to interact with Hydrea. If you have any questions about eating certain foods with Hydrea, talk with your doctor.
Hydrea and lab tests
Before having these lab tests, be sure your doctor knows that you take Hydrea. This will help them correctly interpret your lab test results.
Hydrea and vaccines
Your doctor will likely recommend that you avoid live vaccines while taking Hydrea. You should continue to avoid live vaccines until your doctor says it’s safe to get them.
Live vaccines contain a weakened form of the bacteria or viruses they protect against. While you take Hydrea, your immune system will be weaker than usual. This can increase your risk of an infection from a live vaccine.
Examples of live vaccines include:
The manufacturer of Hydrea hasn’t provided recommendations about inactive (non-live) vaccines. These vaccines don’t contain any active forms of bacteria or viruses.
Before taking Hydrea, talk with your doctor about whether you’re due for any vaccines. They can suggest the best time for you to receive them before you start Hydrea treatment.
You should take Hydrea according to the instructions your doctor gives you.
Hydrea comes as an oral capsule that you swallow. Be sure to wash your hands before and after handling the capsules. Also, you should not take any Hydrea capsules that are broken, opened, or otherwise damaged. Doing so can increase your risk of certain side effects, such as other skin cancers.
When to take
The manufacturer of Hydrea hasn’t provided specific recommendations for when to take the drug. Your doctor will advise you on a Hydrea dosing schedule.
To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.
Accessible labels and containers
If your prescription label is hard to read, talk with your doctor or pharmacist. Some pharmacies offer labels that have large print, Braille, or a code you scan with a smartphone to convert text to speech. If your local pharmacy doesn’t have these options, your doctor or pharmacist may be able to direct you to one that does.
If you have trouble opening medication bottles, ask your pharmacist if they can put Hydrea in an easy-open container. They also may be able to recommend tools that can make it simpler to open lids.
Taking Hydrea with food
You can take Hydrea with food or without it.
Can Hydrea be crushed, split, or chewed?
No, you should not crush, split, or chew Hydrea capsules. In fact, doing so can be dangerous. You should swallow them whole.
If you have trouble swallowing Hydrea capsules, talk with your doctor or pharmacist.
It may not be safe to take Hydrea during pregnancy. It’s known that the drug can harm a fetus because of the way Hydrea works in the body.
Animal trials have shown harm to offspring born to animals that were given the drug during pregnancy. However, keep in mind that animal trials don’t always predict what happens in humans.
If you’re able to become pregnant, your doctor will likely order a pregnancy test for you before you start taking Hydrea. This allows them to confirm you aren’t pregnant.
If you’re pregnant or planning to become pregnant, talk with your doctor before starting Hydrea treatment. Be sure to tell them right away if you become pregnant while taking the drug.
Hydrea and fertility
Hydrea may affect fertility (the ability to conceive a child) in males.*
If you and your partner are planning a pregnancy or have concerns about fertility, talk with your doctor before starting Hydrea treatment.
* Sex and gender exist on spectrums. Use of the term “male” in this article refers to sex assigned at birth.
Hydrea may not be safe to take during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re taking Hydrea.
For more information about taking Hydrea during pregnancy, see the “Hydrea and pregnancy” section above.
If you or your sexual partner can become pregnant, you should use an effective form of birth control during Hydrea treatment. Females* should continue to use birth control for at least 6 months after their last dose of the drug. Males* should continue to use birth control for at least 1 year after their last dose of the drug.
* Sex and gender exist on spectrums. Use of the terms “female” and “male” in this article refers to sex assigned at birth.
It may not be safe to breastfeed while taking Hydrea. The drug can pass into breast milk, which can cause side effects in a child who is breastfed.
For this reason, your doctor will likely recommend that you avoid breastfeeding while taking Hydrea.
If you’re breastfeeding or planning to do so, talk with your doctor. They can suggest other ways to feed your child while you’re taking Hydrea. They may also recommend a different cancer treatment.
This drug comes with several precautions.
Before taking Hydrea, talk with your doctor about your health history. Hydrea may not be right for you if you have certain medical conditions or other factors affecting your health. These include:
- Radiation therapy. Before taking Hydrea, tell your doctor if you’ve had radiation therapy in the past. Hydrea can cause radiation dermatitis in people who have received radiation therapy. Your doctor can help determine if it’s safe for you to take Hydrea.
- Blood cell problems. Taking Hydrea can cause blood cell problems, such as low levels of red or white blood cells. If you already have blood cell problems, tell your doctor before you begin taking Hydrea. Usually, these problems need to be treated before you can start taking Hydrea.
- Allergic reaction. If you’ve had an allergic reaction to Hydrea or any of its ingredients, your doctor will likely not prescribe Hydrea. Ask them what other medications may be better options for you.
- Pregnancy. It may not be safe to take Hydrea during pregnancy. For more information, see the “Hydrea and pregnancy” section above.
- Breastfeeding. It may not be safe to breastfeed while taking Hydrea. For more information, see the “Hydrea and breastfeeding” section above.
Note: For more information about the potential negative effects of Hydrea, see the “Hydrea side effects” section above.
Taking more than the recommended dosage of Hydrea can lead to serious side effects. Do not take more Hydrea than your doctor recommends.
Symptoms of an overdose can include:
- swelling, soreness, or discoloration of the soles of your feet or palms of your hands
- scaling skin on your feet or hands
- darkened skin
- mouth ulcers (sores)
What to do in case of overdose
If you think you’ve taken too much of this drug, call your doctor. You can also call the American Association of Poison Control Centers at 800-222-1222 or use its online tool. However, if your symptoms are severe, call 911 or your local emergency number, or go to the nearest emergency room right away.
When you get Hydrea from the pharmacy, the pharmacist will add an expiration date to the label on the bottle. This date is typically 1 year from the date they dispensed the medication.
The expiration date helps guarantee that the medication is effective during this time. The
How long a medication remains good to use can depend on many factors, including how and where you store the medication.
You should store Hydrea capsules at a room temperature of 68°F to 77°F (20°C to 25°C). For short periods, such as when traveling, you can keep Hydrea capsules at a temperature of 59°F to 86°F (15°C to 30°C). Be sure to store the capsules in a tightly sealed container away from light. Avoid keeping this medication in areas where it could get damp or wet, such as bathrooms.
If you no longer need to take Hydrea and have leftover medication, it’s important to dispose of it safely. This helps prevent others, including children and pets, from taking the drug by accident. It also helps keep the drug from harming the environment.
This article provides several useful tips on medication disposal. You can also ask your pharmacist for information about how to dispose of your medication.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.