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Siklos

Generic Name: Hydroxyurea Tablets (hye droks ee yoor EE a)
Brand Name: Siklos

Medically reviewed by Drugs.com. Last updated on Jun 29, 2019.

Warning

  • This medicine may lower the ability of your bone marrow to make blood cells that your body needs. This can lead to very bad and sometimes deadly bleeding problems or infections. Tell your doctor right away if you have signs of infection like fever, chills, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, a wound that will not heal; any bruising or bleeding; or if you feel very tired or weak.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • This medicine may raise the chance of getting cancer. A type of cancer called leukemia and skin cancer have happened in people taking this drug for a long time. You will need to have regular check-ups. Your doctor will tell you how often to have these. Talk with the doctor.
  • Avoid sun, sunlamps, and tanning beds. Use sunscreen and wear clothing and eyewear that protects you from the sun.

Uses of Siklos:

  • It is used to treat sickle cell anemia.
  • It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take Siklos?

  • If you have an allergy to hydroxyurea or any other part of this medicine (Siklos).
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have any of these health problems: Anemia (other than sickle cell anemia); bone marrow problems like low platelet count, low red blood cell count, or low white blood cell count; or wounds on the legs (leg ulcers).
  • If you are taking any of these drugs: Didanosine or stavudine.
  • If you are breast-feeding. Do not breast-feed while you take this medicine (Siklos).

This is not a list of all drugs or health problems that interact with this medicine (Siklos).

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this medicine (Siklos) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Siklos?

  • Tell all of your health care providers that you take this medicine (Siklos). This includes your doctors, nurses, pharmacists, and dentists.
  • You may have more chance of getting an infection. Wash hands often. Stay away from people with infections, colds, or flu.
  • You may bleed more easily. Be careful and avoid injury. Use a soft toothbrush and an electric razor.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take this medicine (Siklos).
  • Talk with your doctor before getting any vaccines. Use of some vaccines with this medicine (Siklos) may either raise the chance of an infection or make the vaccine not work as well.
  • Severe pancreas, liver, and nerve problems have happened when this medicine (Siklos) was taken with certain drugs used to treat HIV. Sometimes, this has been deadly. If you have questions. Talk with the doctor.
  • If you have had or will be having radiation treatment, talk with your doctor. Worse side effects from radiation treatment have happened with this medicine (Siklos).
  • Allergic reactions have happened with this medicine (Siklos). Sometimes, these have been very bad and people have had to go to the hospital. Talk with the doctor.
  • If you are 65 or older, use this medicine (Siklos) with care. You could have more side effects.
  • This medicine may affect sperm in men. This may affect being able to father a child. Talk with the doctor.
  • This medicine may cause harm to an unborn baby. A pregnancy test will be done before you start this medicine (Siklos) to show that you are NOT pregnant.
  • Women must use birth control while taking this medicine (Siklos) and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
  • Men with a partner who may get pregnant must use birth control while taking this medicine (Siklos) and for some time after the last dose. Ask your doctor how long to use birth control. If your partner gets pregnant, call the doctor right away.

How is this medicine (Siklos) best taken?

Use this medicine (Siklos) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Take this medicine (Siklos) at the same time of day.
  • Take with or without food.
  • Take with a full glass of water.
  • The tablets may be split based on the dose that is needed. If splitting the tablets, only split on the score line.
  • If you cannot swallow tablets, they can be dissolved in a small amount of water in a teaspoon. After mixing, take your dose right away. Do not store for future use.
  • Wash your hands before and after use.
  • Keep taking this medicine (Siklos) as you have been told by your doctor or other health care provider, even if you feel well.
  • You will need to take special care when handling this medicine (Siklos). Check with the doctor or pharmacist to see how to handle this medicine (Siklos).
  • Wear gloves when touching this medicine (Siklos).
  • If a tablet is crushed, do not touch it. If a crushed tablet is touched or gets it in the eyes, wash hands or eyes right away.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Change in color or size of a mole.
  • A skin lump or growth.
  • Change in skin or finger nails.
  • Skin ulcers and dead body tissue (gangrene) has happened with this medicine (Siklos). Call your doctor right away if you have skin ulcers or any other skin changes.
  • Some people have had lung problems with this medicine (Siklos). Sometimes, this has been deadly. Call your doctor right away if you have signs of lung problems like shortness of breath or other trouble breathing, cough that is new or worse, or fever.

What are some other side effects of Siklos?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Siklos?

  • Store at room temperature.
  • Keep lid tightly closed.
  • Store in a dry place. Do not store in a bathroom.
  • If you have split the tablets, store the smaller parts in the bottle. Use the smaller parts within 3 months.
  • You must handle and throw away this medicine (Siklos) the right way. If powder from a broken tablet is spilled, wipe it up with a damp paper towel. Throw away the towel in a closed holder, such as a plastic bag. Wash your hands fully.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

Consumer information use

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this medicine (Siklos), please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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