What Causes Frequent Fluctuation In The Body Temperature?

I am quite often hot and then sometimes I get chills after the hot goes away. I always thought it was my hormones, wrong, my hormones are perfect. Most of the hot feelings are from the middle of my chest up to my face. I m checking my drugs to see if they are a problem, right now I don t see a problem with any of them causing this heat. I change clothes several times a day to adjust to my body temperature.I will be going to my Dr. soon to discuss this problem.Thank you.Joyce