Ephedrine -- Staying in your blood stream

[zbrewha863]

Someone asked a question about how long ephedrine will stay in your blood stream. While I have seen everywhere from 2-7 days after continuous use, I thought I would do a quick check to see how long it actually stays. This is in no way conclusive, but these are the facts I could dig up with a quick search. Please comment.

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From a scientific perspective, the half-life of ephedrine is not entirely certain in the human body, but the half-life of ephedrine taken as part of a normal EC stack (Bronkaid and caffine) is almost completely uncertain -- the only thing they really know is that it is prolonged.

For instance, here's a Merck study where the demonstrated half-life varies between 2-21 hours based on urine acidity. http://www.merckvetmanual.com/mvm/in.../bc/214007.htm

However, and this is the important part for our purposes, this study talks about the effects of ephedrine as infused with beta agonists: Choo J, Horan M, Litlle R, and Rothwell N. Anabolic effects of Clenbuterol on skeletal muscle are mediated by beta2-adrenoreceptor activation. Am J Physiol 1992; 263:E50-E56.

Basically, infusing ephedrine into a beta agonist greatly prolongs the half-life of ephedrine. There are obvious reasons why this would be a beneficial result for someone producing beta agonists. However, every clinical study I've ever seen on "E/C stacks" uses pure ephedrine and caffine.

If you've ever taken pure ephedrine and caffine (or talk to people who have), they will tell you that the results basically suck compared to a "normal" E/C stack of Bronkaid and caffine. This is because ephedrine absorbs rapidly into the blood stream, so you get a big rush, but then it leaves quickly as well -- you're left with this rollercoaster effect that is not very beneficial for your body.

Infusing it with a beta agonist allows long, slow reception and prolongs the half-life of ephedrine significantly. This has to do with ephedrine binding to beta receptors, yada yada, you see where I'm going. The study basically said that the half-life becomes indistinguishable from the half-life of the beta agonist.

So you are correct if you are talking about pure ephedrine and caffine -- it has a short half-life. That is, as far as I can tell, the main reason why people who buy pure ephedrine for E/C stacks have horrible results, while those who buy beta agonists (like Bronkaid) with ephedrine in it for E/C stacks have very good results.

However, there is another point that should be made. There are many studies that show the half-life of renally-excreted substances varies depending on the amount and duration of use. All these studies conclusively show is that the more you take, and the longer you take, a renally-excreted substance, the longer it ends up staying in your system.

Let's take a very easy example -- alcohol. Your body metabolizes alcohol at approximately one drink per hour. If you have one drink per hour, every hour, your body will continue to metabolize them (unless your liver or kidneys fail) normally, and if you test your blood at the end of every hour, you would have little to know trace of alcohol in your blood. Obviously this is an average, and is greatly effected by personal circumstances. But say you drink 3 drinks per hour for 2 hours. At the end of those two hours, your body can only metabolize 2 of those drinks, so you still have four left in your system. If you have 3 drinks per hour for 12 hours . . . well you see where I'm going.

Ephedrine is the same way. It is renally excreted, which means that it has to be processed through the kidneys and excreted in your urine. That is why, under the Merck study referenced above, the half-life of ephedrine (taken in 12mg doses) varies from 2-21 hours depending on urinary pH.

So if you have bad kidneys, or overload your kidneys, it will take much longer for your body to flush the ephedrine. Compound this with the effect of infusing ephedrine in beta agonists, and you have a situation where ephedrine could stay in your body for days beyond its chemical half-life.

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Cliffs:
-- Depends on your kidney function, can take anywhere from 2-21 hours to flush by itself
-- Longer if you take it as part of a beta agonist (e.g. Bronkaid)

[MikeK46]

2-21 hours is a pretty wide gap

I'm more interested in whether or not grinding the Bronkaid into a powder before consuming it (to increase the speed at which it is absorbed into the blood stream) will be beneficial to the effect of the stack. And whether it makes a difference taking caffeine in pill (slower absorption) vs. capsule (faster absorption) form.

[zbrewha863]

One of the studies above (and another one I did not cite) talk about that. Ideally, you want slow absorbtion in order to regulate hormone levels, heart rate, blood pressure, and the like. Ephedrine naturally absorbs extremely fast (30-60 minutes), so with faster-absorbing ephedrine methods you get a big effect in the first hour or so after you take it, which dramatically tapers off after the first hour.

There is a study comparing ephedrine to Clen, and the study basically shows that while an EC stack is much more effective (people on the EC stack lost more fat and retained more muscle), Clen absorbs much slower and so your hormone levels, BP levels, heart rate, etc. remain more stable. This is important for your long-term health.

They did not test different methods of caffine absorbtion, but the results should coincide with the ephedrine since the goal is to mix them simultaneously.

[MikeK46]

Ephedrine naturally absorbs extremely fast (30-60 minutes), so with faster-absorbing ephedrine methods you get a big effect in the first hour or so after you take it, which dramatically tapers off after the first hour.

For long term health of the adrenal glands, it does seem reasonable that slower ephedra uptake & stimulation of receptors would slow downregulation of the receptors.

But as for fat burning...the real question is what effect the varying absorption rates (and therefore level of stimulation of beta-receptors) have on subsequent release of epinephrine and norepinephrine. In other words, is it more effective for fat loss to spike those hormones several times a day, or keep them more stable and consistent? Or, does it not make a difference?

[Transhumanist]

So how long can ephedrine still be detected in your system for sporting event drug tests for example?