I have been taking Singulair for a year now and although I was pr...

I have been taking Singulair for a year now and although I was prescribed it for seasonal asthma and allergies, I am not really sure I needed the medication. I am 37 and live in an area with a lot of sage brush and was having trouble taking full breaths and/or catching my breath. I have taken this medication faithfully for 12 months and after reading some of the posts on here, I can relate to some of them in a mild fashion. I am wondering though, my lack of ability to catch my breath or take a full breath happens more regularly, is this an actual side effect of the medication? Does anyone else experience this? I am very interested in knowing. Thanks!