Generic Name: Zileuton

  • What is Zyflo?

    Zyflo is a medicine that is used to prevent asthma attacks and for long-term management of asthma in adults and children 12 years and older. Zyflo blocks the production of leukotrienes. Leukotrienes are substances that may contribute to your asthma. Zyflo is not a rescue medicine (it is not a bronchodilator) and should not be used if you need relief right away for an asthma attack.
  • What is the most important information I should know about Zyflo?

    Zyflo is not a bronchodilator and should not be used to relieve an asthma attack that has already started. The most serious side effect of Zyflo is potential elevation of liver enzymes and liver problems. While taking Zyflo, you must visit your doctor for liver enzyme tests on a regular basis.
  • Who should not take Zyflo?

    You should not use Zyflo if you ever had an allergic reaction to any of its ingredients. Do not use Zyflo if you have active liver disease or if repeated blood tests show elevated liver enzymes.
  • What should I tell my doctor before I take the first dose of Zyflo?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Zyflo. Also, talk to your doctor about your complete medical history, especially if you have ever had liver problems, including hepatitis, jaundice (yellow eyes or skin), or dark urine; drink alcohol (tell your healthcare provider how much and how often you drink alcohol); are pregnant or planning to become pregnant; or you are breastfeeding
  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Adults and children 12 years and older: The usual dosage is one 600-milligram (mg) tablet four times a day, for a total daily dose of 2,400 mg.

  • How should I take Zyflo?

    Take Zyflo exactly as prescribed by your healthcare provider. Do not decrease the dose of Zyflo or stop taking the medicine without talking to your healthcare provider first, even if you have no asthma symptoms. For Zyflo to help control your asthma symptoms, it must be taken every day as directed by your doctor. While taking Zyflo, it is important to keep taking your other asthma medicines as directed and to follow all of your doctor's instructions.

    Take Zyflo four times a day with or without food. It may be easier to remember to take your medication if you make it part of your daily routine such as with meals and at bedtime. When you take your dose of Zyflo, the tablets may be swallowed whole or split in half to make them easier to swallow.

  • What should I avoid while taking Zyflo?

    Do not miss any doctor's appointments and be sure to follow all instructions. Have blood tests done as ordered by your doctor to check your liver enzymes.
  • What are possible food and drug interactions associated with Zyflo?

    If Zyflo is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Zyflo with propranolol, theophylline, warfarin, or alcohol.
  • What are the possible side effects of Zyflo?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: abdominal pain, upset stomach, nausea

    Serious side effects include liver problems that may be associated with symptoms such as pain on the right side of your abdomen (stomach area), nausea, tiredness, lack of energy, itching, yellow skin or yellow color in the whites of your eyes, dark urine, or flu-like symptoms. Tell your doctor right away if you experience any of these symptoms.

  • Can I receive Zyflo if I am pregnant or breastfeeding?

    The effects of Zyflo during pregnancy and breastfeeding are unknown. This medication should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus. Tell your doctor immediately if you are pregnant or plan to become pregnant. It is not known if Zyflo passes into breast milk. You and your healthcare provider should decide if you will take Zyflo or breastfeed.
  • What should I do if I miss a dose of Zyflo?

    If you miss a dose, take your next scheduled dose when it is due. Do not double the dose.
  • How should I store Zyflo?

    Store at room temperature away from light.