with one dose in the morning for several days, adding a second dose as tolerance increases, and
finally the third dose. Some authors suggest a 5 day on, 2 days off dosing pattern although no
research exists to support this recommendation (19). Individuals on a CKD may wish to
discontinue ephedrine during the carb-up.
Other compounds to enhance the ECA stack
The ECA stack can be potentiated by at least one other compound: the amino acid L-
tyrosine. This may allow less ephedrine to be taken, further minimizing side effects, while
maintaining the thermogenic effects. Although the addition of yohimbe to the ECA stack has
been suggested, the potential for a negative reaction (discussed below) from this combination
contraindicates using them together.
L-tyrosine
L-tyrosine is an amino acid used in the synthesis of adrenaline and noradrenaline.
Additionally L-tyrosine is important for synthesis of the thyroid hormones (1). In theory, adding
it in supplemental form could further improve the thermogenic effect of the ECA stack. In
animal models, injection of ephedrine and L-tyrosine improves the thermogenic effect over
ephedrine alone but it remains to be seen if the same synergistic effect will be seen in humans
(22). Anecdotally most individuals report a greater ‘kick’ from the ECA stack when L-tyrosine is
added. The typical dose of L-tyrosine is 500-1000 milligrams taken with the ECA stack.
Section 3: Yohimbe
As discussed in section 1, one approach to fat loss is to block the alpha-adrenoreceptors,
specifically the alpha-2 adrenoreceptors (2). The herb yohimbe may act in this fashion, giving it
a potential role in aiding fat loss (2). Like ephedrine, yohimbe may work through both direct and
indirect methods. Directly, it may inhibit the effects of alpha-2 receptors, enhancing fat loss.
Indirectly, it may stimulate the release of noradrenaline from nerve endings, stimulating fat
breakdown (23-25). It appears that, at the doses seen in humans, most of the effects of
yohimbine are through the indirect mechanism of increased adrenaline release, rather than by
direct binding to alpha-2 receptors (23-25).
Yohimbe by itself
The primary use of yohimbe for fat loss has been in women although some men have
reported good results. Since the combination of yohimbe with ECA cannot be recommended
because of the potential for side effects, the use of yohimbe by itself is discussed here.
As mentioned above, yohimbe blocks alpha-2 receptors with the ultimate result of