What can you take for colds and cough

I tried sugar free Diabetic Tussin and got so sick from it. My stomach burned, my face got hot, I could feel my heart beating and the blood pulsing through my neck. Then the diarrhea started lasted for about 45 minutes. I guess it was dumping I just know since my surgery that is the first time that has happened. I thought I would be safe taking sugar free cough medicine (won't do that again). Congratulations to all new post-ops and all future patients. Best thing I have ever done what a difference 83 pounds can make.