My son is 4 years old and he's been having this cough with mucus for a while. Every time he coughs, I can feel and hear the mucus in his lungs, but it just won't come out. It's really worrying me. Our doctor suggested giving him Montair LC Kid syrup for four days, and mentioned that if things don't get better, we'd have to try nebulization. When I looked up Montair LC, it seemed to be more for allergies or asthma. Is it really safe to give him this syrup, and will it actually help with the mucus in his chest?

Yes ,continue same treatment.