Montelukast is in a class of medications called leukotriene receptor antagonists. It works by blocking the action of leukotrienes, substances in the body that cause the symptoms of asthma and hayfever (allergic rhinitis).

"For people who suffer from chronic health conditions such as asthma and allergies, it is important to have effective and affordable treatment options," said Gregory P. Geba, M.D., M.P.H., director of the Office of Generic Drugs in FDA's Center for Drug Evaluation and Research. "The generic products approved today will expand those options for patients." 2 Montelukast should not be used for relief of a sudden asthma attack. Some side effects of montelukast can be serious. A health care provider should be immediately contacted if any of the following symptoms are experienced: behavior and mood-related changes such as aggression, depression, or hallucinations; feeling of "pins and needles" or numbness in the arms or legs; rash; flu-like symptoms; or severe pain and swelling of the sinuses.

In clinical trials, the most common side effects reported by patients using Singulair included: upper respiratory infection, fever, headache, sore throat, cough, stomach pain, diarrhea, ear ache, flu, runny nose, and sinus infection.

Apotex Inc., Aurobindo Pharma, Endo Pharmaceuticals, Glenmark Generics, Kudco Ireland Inc., Mylan Inc., Roxane Laboratories, Sandoz Inc., Teva Pharmaceuticals Inc., and Torrent Pharmaceuticals have gained FDA approval for generic montelukast tablets. Apotex, Aurobindo, Endo, Kudco, Mylan, Roxane, Sandoz, Teva, and Torrent have received approval for chewable tablets. Teva has received approval for the oral granule form.

Information about the availability of generic montelukast sodium can be obtained from the manufacturers.

Generic drugs approved by FDA are of the same high quality and strength as brand-name drugs. The generic manufacturing and packaging sites must pass the same quality standards as those for brand-name drugs.

FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation's food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.