Medically reviewed on July 4, 2018
Uses of Zyflo CR:
- It is used to treat or prevent asthma.
- Do not use Zyflo CR (zileuton extended-release tablets) to treat an asthma attack. Use a rescue inhaler. Talk with your doctor.
What do I need to tell my doctor BEFORE I take Zyflo CR?
For all patients taking Zyflo CR (zileuton extended-release tablets):
- If you have an allergy to zileuton or any other part of Zyflo CR (zileuton extended-release tablets).
- 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: Active liver disease or a rise in liver enzymes.
- If you are taking terfenadine.
- If you are breast-feeding or plan to breast-feed.
- If your child is younger than 12 years of age. Do not give Zyflo CR (zileuton extended-release tablets) to a child younger than 12 years of age.
This is not a list of all drugs or health problems that interact with Zyflo CR (zileuton extended-release tablets).
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 CR (zileuton extended-release tablets) 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 CR?
- Tell all of your health care providers that you take Zyflo CR (zileuton extended-release tablets). 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.
- This medicine may affect how much of some other drugs are in your body. If you are taking other drugs, talk with your doctor. You may need to have your blood work checked more closely while taking Zyflo CR (zileuton extended-release tablets) with your other drugs.
- If you are 65 or older, use Zyflo CR (zileuton extended-release tablets) with care. You could have more side effects.
- Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using Zyflo CR (zileuton extended-release tablets) while you are pregnant.
How is this medicine (Zyflo CR) best taken?
Use Zyflo CR (zileuton extended-release tablets) as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take Zyflo CR (zileuton extended-release tablets) within 1 hour after meals.
- Swallow whole. Do not chew, break, or crush.
- To gain the most benefit, do not miss doses.
- Keep taking Zyflo CR (zileuton extended-release tablets) as you have been told by your doctor or other health care provider, even if you feel well.
- Take even during sign-free periods.
What do I do if I miss a dose?
- Skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
See also: Dosage Information (in more detail)
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.
- Signs of low mood (depression), thoughts of killing yourself, nervousness, emotional ups and downs, thinking that is not normal, anxiety, or lack of interest in life.
- Not able to sleep.
- Change in the way you act.
- Very bad and sometimes deadly liver problems have happened with Zyflo CR (zileuton extended-release tablets). Call your doctor right away if you have 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.
What are some other side effects of Zyflo CR?
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:
- Upset stomach.
- Nose or throat irritation.
- Signs of a common cold.
- Muscle pain.
- Loose stools (diarrhea).
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.
See also: Side effects (in more detail)
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 Zyflo CR?
- Store at room temperature.
- Protect 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
- 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 Zyflo CR (zileuton extended-release tablets), 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.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
More about Zyflo CR (zileuton)
- Zyflo CR Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Drug Images
- Drug Interactions
- Pricing & Coupons
- En Español
- 1 Review
- Generic Availability
- Drug class: leukotriene modifiers
Other brands: Zyflo