Singulair Long-Term Side Effects

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Singulair is a prescription drug created to assist in the long-term prevention of asthma as well as relieving stuffy nose and sneezing from allergies. Ingested in either tablet, granule or chewable tablet form, the formula is given to both children and adults to help reduce swelling that closes up airways. By relaxing the bronchial walls, the formula helps the patient breathe without restriction. Singulair is generally tolerated well by users, according to, especially when instructions are followed to the letter. But as with many prescription drugs, side effects have been noted.

Case Studies

Clinical trials have been created to study the possible side effects produced by both short- and long-term use of the product. These trials were created using one group to take the drug and documenting their reactions. The information was compared to a second group that was not taking the drug.

Clinical Trial Results

In one clinical trial studying 2,950 people from age 15 and older, reports, only 1 percent was diagnosed with side effects after taking Singulair for a specific length of time. Some of the side effects included headaches, stomach pain, heartburn, flu symptoms, cough, dizziness and the sensation of weakness. Other symptoms included laryngitis, tonsillitis, pink eye and digestive disorders. Skin disorders were also noted as a possible occurrence such as itching and swelling due to rashes or hives, Younger people seemed more prone to fever, sore throat, diarrhea, and sinus, ear, or tooth infection.

More Severe Reactions

Other clinical trials have revealed more severe reactions from people with low tolerance to Singulair. These reactions include an increased tendency toward bleeding, joint pain and muscle cramping, as well as mood and behavioral fluctuations. One of the most severe reactions to the drug is the occurrence of Churg-Strauss, a rare autoimmune disease that creates asthma and other pulmonary complications, neuropathy (which can lead to damage of the nerves), and inflammation of the blood vessels, according to Liver damage is also a possible side effect caused by Singulair, whereby skin and eyes look yellow, urine becomes dark and there is the possibility of upper abdominal pain indicating the problem, according to eMedTV. Hallucinations and seizures have shown up rarely, as have a worsening of asthma and allergy symptoms.

The Good News

Most people have demonstrated a very positive reaction to Singulair, with no side effects whatsoever, according to clinical trial results submitted to the Food and Drug Administration by Singulair's manufacturer, Merck. It is only in rare cases that the drug is not tolerated. A good health care provider should keep a close eye on your progress with the drug, whereby any slight reactions should be monitored and noted so that if there is a problem, you can be taken off the drug immediately.

One Last Note

Though Singulair is considered an excellent choice for treating asthmatic symptoms, the manufacturer warns that it will not stop an asthma attack.