Zileuton

About Zileuton

Zileuton blocks 5-lipoxygenase, the enzyme that makes leukotrienes, signals that narrow the airways and increase swelling and mucus. Taken daily alongside other asthma medicines, it helps prevent wheezing, coughing and chest tightness. It does not open the airways during an attack, so a quick-relief inhaler is still needed; needing it more often than usual calls for medical advice, and other asthma medicines are not cut back unless the prescriber says so.

The main risk is liver injury. It is not used with active liver disease or liver enzymes persistently at least three times its upper limit of normal. ALT is checked before starting, monthly for three months, every two to three months for the rest of the first year, then periodically. It is stopped for signs of liver trouble, such as upper right abdominal pain, nausea, tiredness, itching, yellow skin or eyes, dark urine or flu-like symptoms, or if ALT reaches five times its upper limit. Women 65 and older, heavy drinkers and people with past liver disease need extra care.

Sleep problems and mood or behavior changes have been reported; MedlinePlus lists agitation, anxiety, depression, hallucinations and suicidal thoughts among changes to report at once. Sinusitis, nausea and sore throat are common. The immediate-release Zyflo tablet, taken four times a day, is also listed by the FDA as discontinued, and no generic of it appears on DailyMed.

Taking Zileuton

How to take it

Two 600 mg tablets twice a day, within one hour after the morning and evening meals. Swallow them whole; do not chew, cut or crush them. Keep taking it on days without symptoms, and keep your quick-relief inhaler for attacks.

If you miss a dose

The label for the extended-release tablets says to take the next dose at the usual time and not to double the dose.

Storage

At room temperature, protected from light, in a tightly closed container out of reach of children.

Interactions to know about

Zileuton roughly doubles theophylline levels, so the theophylline dose is cut by about half at the start and blood levels are checked. It raises warfarin’s effect, so the prothrombin time (INR) is monitored, and doubles propranolol exposure, so that dose may need lowering. Check with the prescriber before starting or stopping any medicine; heavy drinking adds to the liver risk.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Zileuton differs from pharmacy to pharmacy

With the brand gone, every fill is a generic from one of a handful of makers. A pharmacy that does not stock zileuton has to order it and may price it as a slow-moving item, while one that stocks it routinely can quote less.

At two tablets twice a day, a month is a full bottle of 120, so small differences per tablet add up; the ALT tests, monthly at first, are a separate cost.

Ways to pay less for Zileuton without insurance

• If the prescription names Zyflo CR, ask the prescriber to allow generic substitution, since the brand is discontinued.
• Compare more than one pharmacy, and confirm stock before the prescription is sent.
• Once your liver tests are settled, ask the prescriber whether a ninety-day supply is appropriate.
• If cost is a barrier, ask the prescriber whether another asthma controller would suit you.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Zileuton

1. 1.When are my liver blood tests due?
2. 2.Which liver symptoms mean I should call at once?
3. 3.Does it change my theophylline, warfarin or propranolol dose?
4. 4.What should I use during an asthma attack?
5. 5.Which mood or sleep changes should I report?

Related medications