Meds under 2

My child has been sick and congested for the longest time now, we have went to the doctors and they have said let it run its course. However we have tried honey for the cough, herbal tees, steam from hot showers, vaporizers, and humidifiers. Have any parents ever tried a low dose of children's mucinex or other cold medicines? I did not say I was going to give her any. I was just wondering if anyone has tried it ?