Hi, I Am 66 And Have Been Taking The No

Hi, I am 66 and have been taking the no name brand Montelusk (Singulaire) for the past 10 years at least.
I used to have the problem of constantly trying to clear my throat numerous time a day and was bad enough that my wife and younger kids at the time kept telling me to stop! The proble was that I could not get it up but if I worked hard enough I could keep it down without it choking. I then was prescribed Singulaire and almost immediately all the symptoms were gone by taking 1 pill per day and there was no benefit to take more than one. The doctor was entirely correct and now years later it still works, but my senior Pharmacare will not cover it as Singulaire is supposed to be for allergies only so I am out of luck and the medication is not cheap. I also have a mild case of a-fib would this be a good factor to continue taking this medication.
Thanks Alan