Products
Zileuton is commercially available in the United States in tablet and powder form (Zyflo). It is not currently approved in many countries.
Structure and properties
Zileuton (C11H12N2O2S, Mr = 236.3 g/mol) is an almost odorless, white, crystalline powder that is practically insoluble in water. It exists as a racemate. Both enantiomers are pharmacologically active.
Effects
Zileuton is anti-inflammatory, antiasthmatic, and antiallergic. It is a specific inhibitor of 5-lipoxygenase, thus inhibiting the formation of leukotrienes (LTB4, LTC4, LTD4, and LTE4). These are inflammatory mediators involved in the development of inflammation, edema, mucus formation, and bronchoconstriction in the airways.
Indications
For the treatment of chronic bronchial asthma.
Dosage
According to the SmPC. Zileuton has a short half-life and therefore must be administered four times daily. However, sustained-release dosage forms have been developed that must be taken less frequently.
Contraindications
Zileuton is contraindicated hypersensitivity, acute liver disease, and elevation of transaminases. For complete precautions, see the drug label.
Interactions
Drug-drug interactions have been described with theophylline, warfarin, propranolol, and terfenadine.
Adverse effects
The most common possible adverse effects include headache, pain, abdominal pain, weakness, injury, dyspepsia, nausea, and muscle pain.
