Singulair's generic name is montelukast. It is used to prevent asthma attacks in adults and children as young as 12 months old. It is also used to treat symptoms of year-round (perennial) allergies in adults and children who are at least 6 months old and symptoms of seasonal allergies in adults and children who are at least 2 years old.
Call your doctor at once if you have a serious side effect such as:
-skin rash, bruising, severe tingling, numbness, pain, muscle weakness;
-mood or behavior changes, anxiety, depression, or thoughts about suicide or hurting yourself;
-tremors or shaking;
-easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;
-severe sinus pain, swelling, or irritation;
-worsening asthma symptoms; or
-severe skin reaction -- fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.
Less serious side effects of montelukast may include:
-stomach pain, heartburn, upset stomach, nausea, diarrhea;
-fever, stuffy nose, sore throat, cough, hoarseness; or