Ephedrine is a naturally occuring
central nervous system stimulant obtained
from the plant
Ephedra equisetina. It is also produced by chemical
synthesis, the synthetic product being marketed in the form of its salt,
ephedrine
sulfate; it occurs as a white crystalline powder with a bitter
taste, soluble in water and very soluble in
alcohol. Ephedrine is closely
related in structure to
methamphetamine, although its
CNS actions are much
less potent and also longer-acting than those of the
amphetamines. Its
peripheral stimulant actions are similar to but less powerful than those of
epinephrine (also called
adrenaline).
Ephedrine is an
adrenergic drug that works by stimulating
alpha
and
beta receptors thus causing the release of
norepinephrine.
Alpha and beta receptors exist in the
sympathetic nervous system,
(fight or flight) and stimulation causes increased heart rate,
bronchodilation, and
vasoconstriction.
(from Drugs and Drug Abuse, 2nd Ed., by: Cox, Jacobs, LeBlanc, Marshman, and Fehr, 1987)
If you're having a problem with
tolerance, make sure you take plenty of
L-Tyrosine which will help build up your
epinephrine stores. Failing that, abstain for a week or so.