<<Disclaimer: Verify this information before applying it to your situation.>> Just contacted the Merck Service Centre at 1 800 672 6372 about Singulair which is a great product for controlling asthma. I have been having a 'gluten' reaction to this medicine. Merck says that if there is starch in any of their meds it is made from corn and contains from .01 to.05% gluten. According to the info sheet, Singulair contains no starch. However, it is producing a reaction. Strange...!! Jessie