Robinchd (Vero Beach, Fl, Usa) on 09/03/2011:

I recently started wondering if I could be allergic to all dairy, as after eating ice cream I cough and have phlegm for 20 minutes or so. It took a week or so, but since I have not had any dairy the coughing and post nasal drip has completely stopped, and my sinus' have not bothered me at all.

I think if people suffering with sinus infections can give up all dairy (it's not easy), but the reward of alleviating sinus problems and sinus infections is so worth it.