RE: Eph and colds
No problem at all
Many cold remedies contain ephedra based ingredients as these help to break down the mucosal bonds, hence the runny nose often seen when on the stuff.
So as far as I know, since it is in many remedies it should not be a problem. as regards increasing body temperature, i can not be sure, but as said is contained in many remedies and so should be safe, also it only needs to increase the body temp for the brown fat, so if your body is already running at a higher temp, I should imagine some physiological system will kick in to prevent it going higher - but cant be sure on the second point