Indications
Zileuton is used for the long-term prevention and control of asthma in adults and children aged 12 years and over. It is a preventer: it does not relieve a sudden asthma attack, for which a fast-acting reliever inhaler is needed.
How It Works
Zileuton blocks 5-lipoxygenase, the enzyme that makes leukotrienes. Leukotrienes are chemicals that narrow the airways, increase mucus and cause swelling in the lungs. Lowering them helps keep the airways open and reduces asthma symptoms.
Dosage and Administration
Extended-release tablets: usually 1,200 mg (two 600 mg tablets) twice a day, within 1 hour after the morning and evening meals, for a total of 2,400 mg a day. Swallow whole; do not chew, crush or split. Immediate-release tablets, where available, are usually 600 mg four times a day. Follow your doctor’s instructions and keep using your other asthma medicines unless told otherwise.
Interactions
Zileuton raises levels of Theophylline (the Theophylline dose usually needs to be halved and blood levels checked), Warfarin (INR needs monitoring) and Propranolol. It may also affect other medicines broken down by the liver enzyme CYP1A2. Tell your doctor about all medicines, including herbal products.
Contraindications
- Active liver disease.
- Liver enzymes (ALT) at least three times the upper normal limit.
- Allergy to Zileuton.
Side Effects
Common side effects include headache, stomach pain, indigestion, nausea, muscle aches and a rise in liver enzymes on blood tests. Some people have sleep problems, mood changes or upper respiratory infections.
Get urgent medical help for signs of liver injury (pain in the upper right abdomen, nausea, unusual tiredness, itching, dark urine, yellowing of the skin or eyes, flu-like symptoms), mood or behaviour changes including thoughts of self-harm, or an asthma attack that does not improve with your reliever inhaler.
Pregnancy and Lactation
There is limited information on use in pregnancy, and animal studies raised concerns; use only if a doctor considers it clearly needed. It may pass into breast milk; breastfeeding is not recommended during treatment.
Precautions and Warnings
Liver function blood tests are needed before starting, regularly during the first months and periodically after that. Use with care if you drink a lot of alcohol or have had liver disease. Do not use it to treat an acute asthma attack, and do not suddenly replace inhaled or oral steroids with it.
Overdose
There is limited experience with overdose. Seek medical help straight away; supportive care will be given and liver tests checked. Take the pack with you.
Therapeutic Class
Antiasthmatic; leukotriene synthesis inhibitor (5-lipoxygenase inhibitor).
Storage
Store below 30°C in a dry place, away from light and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.