Singulair (Montelukast) Asthma Medication Profile

What It Is: Singulair (generic name montelukast sodium) is a prescription asthma medicine, taken by mouth, that is used to prevent and control asthma symptoms. It is a daily controller medicine, which means it does not provide instant relief and cannot be used for asthma attacks.

Singulair is used to treat asthma in both adults and in kids as young as 12 months. This medicine is also used to improve indoor and outdoor allergies in adult and kids. Plus, it may be used to prevent exercise-induced asthma (EIA) in people age 15 years and older.

How It Works: Singulair is a type of asthma medicine called a leukotriene receptor antagonist. Leukotrienes are substances in our bodies thought to cause allergy and asthma symptoms. Singulair blocks the leukotrienes, which helps lessen the frequency and intensity of asthma and allergy symptoms.

Singulair is not an inhaled steroid, so it can be an alternative for people who are not getting adequate control with an inhaled steroid, or who want to avoid steroids for some reason.

Forms & Doses: Singulair is always swallowed orally, rather than breathed in via a mist or powder through an inhaler, as with most asthma medicines. It comes in the following forms:

• Oral Granules (ages 12 months to 5 years)
• Chewable Tablets 4mg (ages 2 to 5 years)
• Chewable Tablets 5mg (ages 6 to 14 years)
• Tablets 10mg (ages 15 and above)

The granules can be sprinkled on applesauce or infant cereal or mixed into a bit of breast milk or baby formula. The chewable tablets, along with the granules, can help get medicine into young kids who can't swallow pills and won't drink liquid asthma medicines.

Singulair is taken once daily, usually in the evening. Or, when used to prevent EIA, it is taken about 2 hours before exercise.

Risks & Side Effects: Most asthma medicines are quite safe to take, even over the long term. But, like most medicines, Singulair can sometimes cause mild, usually short-term, side effects in certain people. Here are the most common side effects:

• stomach pain
• stomach or intestinal upset
• heartburn
• tiredness
• fever
• stuffy nose
• cough
• upper respiratory infection
• dizziness
• headache

Less common side effects include agitation and aggressive behavior, allergic reactions, hives, and itching, bad or vivid dreams, increased bleeding tendency, and bruising.

They might also include diarrhea, drowsiness, hallucinations, hepatitis, indigestion, pancreatitis, irritability, joint pain, muscle aches and muscle cramps, nausea, palpitations, pins and needles/numbness, restlessness, seizures, swelling, trouble sleeping, and vomiting.

Most side effects lessen or go away over time. But, if yours do not, or if they become bothersome, then be sure to call your doctor right away.

Important Update 4/08: Merck & Co., the makers of Singulair, announced recently that patient reports suggest a possible link between taking Singulair and changes in mood and behavior that could lead to suicide.

However, this risk is not great enough to cause the Food & Drug Administration (FDA for short) to take the medicine off the market. Further study will be needed, which can take several months.

If you or your child are taking Singulair, you should not stop taking it before talking to your doctor. But do be on the watch for any signs of mood changes or suicidal thinking.

What You Need to Know: It's important to remember that Singulair is a preventive, or controller medicine. It cannot be used to treat an asthma attack or even acute symptoms, as it will not start working immediately. DO take it every day, about the same time each day, to keep a steady level in your system.

In the latest asthma treatment guidelines, experts emphasize that inhaled steroids, not leukotriene antagonists like Singulair, are the preferred treatment for asthma. When inhaled steroids don't provide adequate control, the guidelines recommend that a long-acting beta agonist be added. Singulair is considered an alternative treatment.

When to Call Your Doctor: It's a good idea to call your doctor any time that you do not have the expected effect from one of your asthma medicines, whether Singulair or something else. In addition, if you have any of the following symptoms, you should call your doctor right away:

• a feeling of pins and needles or numbness of arms or legs
• a flu-like illness
• rash
• severe inflammation (pain and swelling) of the sinuses (sinusitis)

If you'd like to learn more about Singulair, including how it might interact with other medications you are taking, check out the Drugs A to Z page.

Sources: Singulair Patient Information Sheet. http://www.merck.com/product/usa/pi_circulars/s/singulair/singulair_ppi.pdf

NHLBI. National Guidelines for the Diagnosis and Management of Asthma (EPR-3). July 2007. http://www.nhlbi.nih.gov/guidelines/asthma/asthgdln.pdf

FDA. Early Communication About an Ongoing Safety Review of Montelukast (Singulair). <http://www.fda.gov/cder/drug/early_comm/montelukast.htm>