I'm curious what you're running it at onetime...
OK but before I answer I have to explain a few thing, read this if you want to get absolutely shredded. This is why ECA is the best;
The way ECA works is it gives you more energy on less carbs, so say you take 32mg of ephedrine and you have ate 300 grams of carbs, the energy you get from the ECA will NOT be that great, if you ate 200 grams of carbs then the additional energy you get from it ECA will be more, and if you ate 100 grams it will be more yet. On 0 carbs the energy increase is the greatest on ECA. It is almost as if the carbs diminish it's potency.
So it is amazing on a no carb diet. But the problem is people do not know how to use ECA in a maximum beneficial manner so they do not get proper results. First mistake is they take it daily and periodically, huge mistake, your receptors get used to the stimulants fast so before you know it you have to keep upping the dose to achieve the same levels of energy it produces.
This is how I use it, only on training days and prior to a workout to start off with, I will take 32mg of ephedrine, 200mg caffeine, and 80mg aspirin 20 minutes before a workout and I am on a no carb diet and the energy from the ECA is NO different from that of having eaten tons of carbs, I swear absolutely no different in energy levels at all, still cranking 400 on the bench for reps no problem.
By only using it when I need it I will not tap out my receptors that quickly and at around the 3 week mark I will take 48mg of ephedrine instead of 32 cause by this point I will need more to achieve the same results.
at the 5 week mark I am up 64 mg at one time and 300mg of caffeine, the aspirin always stays at 80mg cause the body does not adapt to aspirin ( at least not noticeably). Now every 4 workouts I up the ephedrine by 8mg and when I get to the 96mg of ephedrine I add another 100 mg of caffeine. Remember up to this point your primary reason to have used ECA is as a stimulant for your workout and of course there are other secondary benefits as well.
At week six I take 8mg of ephedrine when I wake up and 8mg at launch, at week 7 I take 16mg of ephedrine when I wake up and 16mg at launch, at week 8 I take 24mg of ephedrine when I wake up and so on and so on. Now the primary reason for the ECA in the morning and at launch is for fat burning and to suppress appetite, while your pre-workout ECA still remains as a stimulant.
This is the pattern I use and I lose 40-45 lb in 10-12 weeks, no one loses faster then that, but more importantly I get to 4% or less and this what I put my people on to get shredded, they love it, simple, basic and easy. In fact everyone I have worked with claims the same strength 2 weeks out on no carbs as the day they started dieting because the ECA allows you to throw up your heaviest weights in the gym.
The no carb diet is exactly that, no carbs, unlimited amounts of protein and I go as long as I can (anywhere from 6-10 days) before I carb load with 300 grams and then it's back to the trenches.
Now here is the good part and I swear by this, in fact I put my life on it;
1. unlimited protein and still get contest shredded
2. Ephedrine if and only if taken the sufficient amount will give you the same energy levels in the gym on a no carb diet as if you where eating carbs.
3. No carb diet will make you lose fat until there is no fat left to lose no matter where you start from, even if you have 100lb to lose, it doesn't matter, no plateaus, weight will come off every day no matter what until your shredded.
4. ECA will raise metabolism, burn fat, give you energy, strength and alertness, and suppress your hunger.
Conclusion; take ECA as a stimulant only pre-workout for the first 5 weeks, take ECA as a fat burner and appetites suppressor from week six and on and still also take it as a stimulant. Gradually increase Ephedrine and caffeine as you go, fastest way to get shredded no carb diet and ECA, there is no faster way.