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Zyflo

Generic name: zileuton

What is Zyflo used for?

  • Zyflo is used to treat or prevent asthma.
  • Do not use Zyflo to treat an asthma attack. Use a rescue inhaler. Talk with your doctor.

Before taking Zyflo, tell your doctor:

For all patients taking Zyflo:

  • If you are allergic to Zyflo; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have liver disease or raised liver enzymes.
  • If you are taking terfenadine.

Children:

  • If your child is younger than 12 years of age. Do not give Zyflo to a child younger than 12 years of age.

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

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 Zyflo 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 Zyflo?

  • Tell all of your health care providers that you take Zyflo. This includes your doctors, nurses, pharmacists, and dentists.
  • It may take a few weeks to see the full effect.
  • If you are not able to get a breathing attack under control, get help right away.
  • Call your doctor right away if your breathing problems get worse, if your rescue inhaler does not work as well, or if you need to use your rescue inhaler more often.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • Talk with your doctor before you drink alcohol.
  • If you are 65 or older, use Zyflo with care. You could have more side effects.
  • Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

How is Zyflo best taken?

Use Zyflo as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Take with or without food.
  • Keep taking Zyflo as you have been told by your doctor or other health care provider, even if you feel well.
  • Keep taking Zyflo even when you are not having symptoms.

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 the side effects of Zyflo that I need to call my doctor about immediately?

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.
  • Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Trouble sleeping.
  • Change in the way you act.

What are some other side effects of Zyflo?

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:

  • Headache.
  • Upset stomach.
  • Stomach pain or heartburn.

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 1-800-332-1088. You may also report side effects at https://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.

Zyflo Images

How do I store and/or throw out Zyflo?

  • Store at room temperature protected from light. Store in a dry place. Do not store in a bathroom.
  • 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 and disclaimer

  • 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.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about Zyflo, 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.

This information should not be used to decide whether or not to take Zyflo or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Zyflo. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Source: Wolters Kluwer Health. Last updated April 5, 2023.