My son was put on singular a few weeks ago. He lost 6 lbs in a m...

My son was put on singular a few weeks ago. He lost 6 lbs in a month. There is no reason for that. He was on a trial period for a month and no longer has any pills left. I don't think I want him to go back on them! He is 6 and not very big to begin with and has lots of of ther problems. I don't want the singular to make them worse. What are the possible side effects of SINGULAIR? The side effects of SINGULAIR are usually mild, and generally did not cause patients to stop taking their medicine. The side effects in patients treated with SINGULAIR were similar in type and frequency to side effects in patients who were given a placebo (a pill containing no medicine). The most common side effects with SINGULAIR include: stomach pain stomach or intestinal upset heartburn tiredness fever stuffy nose cough flu upper respiratory infection dizziness headache rash Less common side effects that have happened with SINGULAIR include (listed alphabetically): agitation including aggressive behavior, allergic reactions (including swelling of the face, lips, tongue, and/or throat, which may cause trouble breathing or swallowing), hives, and itching, bad/vivid dreams, increased bleeding tendency, bruising, diarrhea, drowsiness, hallucinations (seeing things that are not there), hepatitis, indigestion, inflammation of the pancreas, irritability, joint pain, muscle aches and muscle cramps, nausea, palpitations, pins and needles/numbness, restlessness, seizures (convulsions or fits), swelling, trouble sleeping, and vomiting. Rarely, asthmatic patients taking SINGULAIR have experienced a condition that includes certain symptoms that do not go away or that get worse. These occur usually, but not always, in patients who were taking steroid pills by mouth for asthma and those steroids were being slowly lowered or stopped. Although SINGULAIR has not been shown to cause this condition, you must tell your doctor right away if you get one or more of these symptoms: 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) These are not all the possible side effects of SINGULAIR. For more information ask your doctor or pharmacist. Talk to your doctor if you think you have side effects from taking SINGULAIR.