Leukotriene Modifiers


Uses of Leukotriene Modifiers

Leukotriene modifiers (LTMs) are medications designed to block a chemical mediator in our body (leukotrienes) that causes mucous production, swelling of the lining of the sinuses and lungs, spasm of the lungs, and recruitment of cells that contribute to allergic inflammation.  Some leukotriene modifiers work by blocking production of leukotrienes while others block the receptor for the inflammatory mediators.

Leukotriene modifiers are approved to treat both nasal allergies and asthma.  Leukotriene Modifiers are available in the form of a pill or chewable tablet, however there is one leukotriene modifier that also comes as granules that can be mixed in food for young children.

Currently available leukotriene modifiers are:

  • Singulair (Montelukast)
  • Accolate (Zafirlukast)
  • Zyflo (Zileuton)

Taking Leukotrience Modifiers

Take this medication exactly as instructed by your physician.  Leukotriene modifiers are used as a preventative for allergy or asthma symptoms and therefore should be taken daily.

Leukotriene Modifiers Side Effects and Warnings


Singulair (Montelukast) is well tolerated, can be taken with most other medications, and has a very good safety profile.

Accolate (Zafirlukast) has been associated with liver damage on rare occasions. If Accolate is taken concurrently with certain other medications, the effects of either drug could be increased, decreased, or altered. It is especially important to check with your doctor before combining Accolate with the following:

  • Aspirin
  • Blood-thinning drugs such as Coumadin
  • Carbamazepine (Tegretol)
  • Cyclosporine (Sandimmune, Neoral)
  • Erythromycin
  • Heart and blood pressure medications called calcium channel blockers, including Calan, Cardizem, and Procardia
  • Phenytoin (Dilantin)
  • Theophylline (Theo-Dur, others)
  • Tolbutamide (Orinase)

Although rare, Zyflo (Zileuton) has been associated with elevations in liver function tests. All patients should have liver functions checked before they start this medication, as well as periodically during its use.  If Zyflo (Zileuton) is taken with certain other drugs, the effects of either could be increased or altered.

It is especially important to check with your doctor before combining Zyflo (Zileuton) with the following:

  • Theophylline
  • Coumadin
  • Propranolol


Overall the most common side effects reported for these medications include:

  • sinusitis
  • upper respiratory infection
  • sinus headache
  • cough
  • nosebleeds
  • headache
  • tiredness
  • stomach ache
  • ear infections


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