Leukotriene modifiers

Description
Leukotrienes are very powerful chemicals released by mast cells in the airways, and they are an important cause of asthma. Medications called leukotriene modifiers (e.g. Accolate® and Singulair®) either interfere with the sequence of chemical reactions that leads to symptoms, or interfere with the binding of leukotrienes with their corresponding receptors and thus limit their ability to cause asthmatic symptoms.

Leukotrienes can be released in sites of allergic inflammation in the nose, sinus mucosa, eyes, lungs and skin. After exposure to allergens or irritants, leukotrienes are released from the mucous membranes of the nose, sinuses and/or chest causing symptoms of swelling and obstruction. This can lead to osteomeatal complex blockage, reduced mucociliary clearance and increased risk for sinusitis.

Leukotriene Modifiers

Brand Name	Generic Name	Dose	Other Instructions
Accolate®	zafirlukast	20mg tablet twice a day	use 1 hour before, or 2 hours after meals
		10mg tablet twice a day (5 - 11 years)
Singulair®	montelukast	10mg tablet once a day, (ages 15 years and older)	not affected by meals
		5mg tablet once a day, (6 - 14 yrs)
		4mg chewable tablet once a day (2 - 5 years)
		4mg granules once a day (12 - 24 months)

Use
Treatment with leukotriene modifiers can improve lung function, decrease the need for sympathomimetic inhalers (e.g. albuterol), and reduce symptoms. Although these medications are effective, they do not appear to be quite as effective as oral or inhaled corticosteroids in controlling asthma. Further, there is no clear evidence that leukotriene modifiers prevent remodeling of the airways as does corticosteroids treatment.

Additionally leukotriene modifiers may be very effective in treating some individuals with asthma, while having little or no effect in others. In contrast, corticosteroids are effective in the vast majority of individuals. That being said, The Asthma Center specialists have found the combination of corticosteroids and leukotriene modifiers to be beneficial. Use of both leukotriene modifiers and corticosteroids can better control asthmatic symptoms than either medication alone in some individuals, while also reducing the dose of corticosteroids needed to achieve good control of asthmatic symptoms.

Leukotriene modifiers have been available since 1997 for the treatment of asthma. By modifying leukotriene effects, these medications reduce the symptoms of allergies, asthma and possibly sinusitis and nasal polyps. Although leukotriene modifiers are used for the treatment of sinusitis and nasal polyps, especially for those with aspirin intolerance, it is an “off-label” use and not yet in alignment with FDA recommendations.

Risks and Precautions
These medications are usually well tolerated. Side effects are uncommon but include: headache, nausea, stomach upset, pain, fever, muscle ache, fatigue, sore throat, laryngitis and liver enzyme elevation. Churg Strauss syndrome, a form of vascular inflammation, rarely is noted with these medications and can include vague symptoms of fever, fatigue, weight loss, vasculitis leading to kidney disease, hypotension, abdominal pain, bowel damage, heart disease, muscle aches and wasting, nervous system damage and arthritis. Liver function abnormalities have been reported with all of these agents and should be periodically monitored.