Ok I Have Just Been Put On A Pill Of

ok I have just been put on a pill of 500m that is two colors and is for sinus problem that i have had for l1 days. I had congestion in my head and had to blow my nose for days with this yellow sticky stuff coming out. I would like a description OF it so I know what I am getting. They have me taking 3 pILLS A DAY FOR TENDAYS . iT STARTS WITH A LETTER am i THINK. iVAN