Singulair and allergies

[Lucy]

I didn't know taking sudafed was a no-no sometimes, why and when is it not okay (I mean is that for asthma or kids?)?
I take generic fexofenadine (spelled wrong). Claritin didn't help at all. My doctor had me take mucinex and sudafed earlier when the evergreen pollen was getting to me.

Make SURE he drinks enough water.

This thread is interesting.