I took Singulair with very good results for two years, but after it went generic, I tried two different company's versions and did not have good results. The first one (I'm pretty sure it was Teva) was disastrous: heart palpitations and shortness of breath. The second--Apotex--is better, but not at all as good as the original brand Singulair. I cannot afford the brand, and my asthma is driving me crazy. Can anyone tell me which of the 10 generics has worked best for you? Thanks so much!