It is not a good idea to use drugs for purposes they were not meant for. Ephedrine is an example of such misuse - it was developed with a different purpose, and if you want to lose fat with it, you will need excessive dosages. This kind of dosages will bring along a lot of side effects. Besides, ephedrine will also eat up your lean mass, not only fat. Therefore, better don't use it for fat loss.
If you want to lose fat, cardarine GW and N2Slin is the best option. They are completely safe, and were specifically developed for recomping (fat loss together with lean mass gains). Therefore, you will get much better results with this stack, and will not experience side effects. Additionally, they will not eat up the lean mass - only fat, and Cardarine will give you a lot of other benefits, such as endurance, cardio and recovery. Cardarine GW and N2Slin is a win-win stack for fat loss and recomping.