Today my Dr. prescribed Cheratussin AC Syrup for me to control this cough I have had for over a week and get this mucus out of my lungs. My question is, I’m taking Tylenol Cold and Flu Severe Liquid for the sore throat and head congestion as well and I just noticed it has Guaifenesin in it, as well as the Cheratussin. Is it SAFE to take both, each one 30 minutes apart, before I go to bed? Thank you!