Ephedrine, when used correctly with caffeine and aspirin (ECA), works well when you follow a proper low fat diet and exercise plan. Too many individuals assume that using ECA alone will promote fat loss. I found that it worked well for me when I used it prior to either workouts, cardio or weights.
Using ECA three times daily will not affect your body's ability of fat metabolism. That is, it will enhance your metabolism but it won't cause your metabolism to cease when used regularly. However, you should test your ability to accept ECA before using it 3 times a day. Though it is recommended, using ECA more than once a day may cause you to have side effects like insomia, jitters, etc. I, personally, cannot use it more than once a day. I work the graveyard shift at my job and have found it to be differcult to sleep after work if I use ECA more than once a day. It gets to the point that I can literally feel my heart pumping at times.
It is also important to note the ephedrine that you are using. There are several types. One type is often known as "mini thins". Those are basically called ephedrine HCL and comes in dosage of 25 mg. Because you should never use more than 75 mg. of ephedrine a day, this is the only safe type to use more than once (if you can tolerate it). The next type of ephedrine are the same size but thicker than ephedrine HCL and are often sold online. They are often in dosages of 30 mg. Lastly, there's efedrina which is larger and comes in dosages of 50 mg.
What you must know about ECA is that you should cycle the use of it. After about 6-8 weeks, you may no longer feel the affect of ECA without increasing the dosage (which is not safe).
Most importantly, before using the ECA stack I would recommend that you have a physician perform a physical check up on you. I know I may sound like some fat loss supplement commercial but, as I stated, it is important. That is because ephedrine can be extremely harmful if you suffer with high blood pressure, diabetes, respiratory problems, heart problems, etc. And pregnant or nursing women are advised not to use ephedrine or ECA.