Has anyone out there found that supplements to speed up metabolism actually slow them down? I react the opposite to supplements and some drugs such as cough medicine that should increase metabolism. I can't remember the name of the phenomena.

If you do, do you know how to handle it? Would something to slow you down help you lose weight?

For instance, I can take cough syrup that is supposed to make people with thyroid disease (which I have) hyper. It doesn't make me hyper or sleepy. I can take over-the-counter stimulants for weith loss such as Green T and gain instead! Any help would be appreciated.