Zileuton(zye loot’ on)
Zyflo, Zyflo CRDNC
PREGNANCY CATEGORY C
Drug Classes
Antiasthmatic
Leukotriene synthesis inhibitor
5-lipooxygenase inhibitor
Therapeutic Actions
Inhibits the enzyme that catalyzes the formation of leukotrienes from arachidonic acid, thus blocking many of the signs and symptoms of asthma (neutrophil and eosinophil migration, neutrophil and monocyte aggregation, leukocyte adhesion, increased capillary permeability, and smooth muscle contraction). These actions contribute to inflammation, edema, mucus secretion and bronchoconstriction caused by cold air challenge in patients with asthma.
Indications
Prophylaxis and long-term treatment of asthma in adults and children 12 yr and older
Contraindications and Cautions
Contraindicated with hypersensitivity to zileuton or any of its components, acute asthma attacks, status asthmaticus, pregnancy and lactation, severe hepatic impairment.
Use cautiously with hepatic impairment.
Available Forms
CR tabletsDNC—600 mg; tablets—600 mg
Dosages
Adults and patients 12 yr and older
CR tablets, 1,200 mg (2 tablets) PO bid within 1 hr after morning and evening meals for a total daily dose of 2,400 mg. Tablets, 600 mg PO four times daily for a total daily dose of 2,400 mg.
Patients with hepatic impairment
Use caution; contraindicated if liver enzymes (AST, ALT) three or more times normal.
