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AUG. 8, 2003 | A study
conducted at the University of Arkansas
for Medical Sciences (UAMS) and reported
in the June 15 issue of
The American Journal of Cardiology
adds more scientific weight to the public
health argument for banning ephedra, the
dietary supplement found in performance
enhancing and weight loss products. The
study showed supplementing with two
Metabolife 356® caplets three times a day
for two weeks had adverse short-term
effects on healthy men.
The study findings appeared
during a year in which calls for the
banning of ephedrine, both at the state
level - in New York, for example - and at
the federal level, have escalated. The
U.S. House of Representatives Committee on
Energy and Commerce conducted two days of
hearings on ephedra July 23-24. Among
those testifying were the parents of
Baltimore Orioles pitcher Steve Bechler,
whose highly publicized death during
spring training in March after taking the
ephedra-containing weight loss supplement
Xenadrine RFA-1® sparked renewed calls for
a ban.
Of the five authors of the
journal article, four are UAMS faculty
members and researchers: Stephanie F.
Gardner, Pharm.D, Ed.D., interim dean of
the
College of Pharmacy and the
study’s lead investigator; Amy M. Franks,
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Pharm.D., assistant
professor in the College of Pharmacy; Bill
J. Gurley, Ph.D., associate professor in
the College of Pharmacy; Bal Krishna
Singh, M.D., assistant professor in the
Division of Cardiovascular Medicine; and
Jawahar L. Mehta, M.D., Ph.D., chair of
the Division of Cardiovascular Medicine.
Christine A. Haller, M.D., of the
University of
California-San Francisco
also is a co-author.
The subjects in the study were 10 men who
did not have a history of taking an
ephedra-containing supplement, did not
smoke, did not have a known medical
condition, and were not using any
prescription or nonprescription medication
at the time of the study. They were
required to refrain from caffeine and
exercise throughout the study period. They
wore monitors to measure their heart rate
and rhythm 24-hours a day, and were
assessed after the third and 14th
days.
“At Day Three, all subjects
reported adverse effects,” the UAMS team
reported. “The most common adverse effects
were dry mouth, shakiness, and insomnia
(day 3), and dry mouth and anxiety (Day
14). Two subjects reported chest pain
during the 14-day study period,” the
article said.
The study showed on the
third day a fivefold increase in the
number of atrial premature contractions (APCs),
which are abnormal cardiac impulses that
have the potential to initiate more
sustained arrhythmias. “Although this can
occur in healthy individuals, the
increased number of APCs after Metabolife
consumption may signify increased risk for
developing more serious cardiac rhythm
disturbances,” Dr. Gardner said.
“Unfortunately, it is impossible to
predict which patients are likely to be
affected.”
Most symptoms were less
severe after Day 14 than after Day Three.
The researchers speculate that may be due
to decreased compliance by the
participants, leading to lower
concentrations of the drug in their
systems, or adaptive changes in the way
their bodies absorbed the substances. In
any case the authors recognized the study
does not conclusively prove statistically
significant differences in cardiac rhythm,
and sets the stage for further
investigation.
”This was a pilot study of
10 healthy people to try to collect enough
preliminary data to show that it is a
worthy thing to investigate,” Gardner
said. “We don’t purport that 10 people is
enough to make major conclusions, but when
you look at 10 people and two of them have
chest pains, and all of them reported
other adverse side effects in a 14-day
period, that’s alarming enough to say this
needs further study.”
Links on This Page:
American Journal of Cardiology:
http://www.cardiosource.com/library/journals/journal?sdid=4876
College of
Pharmacy:
http://www.uams.edu/cop/
Stephanie Gardner, Pharm.D.,
Ed.D., Is Interim Dean of College of
Pharmacy:
http://www.uams.edu/today/2003/041703/Gardner.htm
Herbal Supplements Topic of Old State
House Lecture:
http://www.uams.edu/today/2002/050202/gurley.htm
UAMS Expert on Ephedrine in National
Spotlight:
http://www.uams.edu/today/083001/gurley.htm
Audio – Herbal Supplements:
http://www.uams.edu/htyh/0202/herbal.htm
© 2003 University of
Arkansas for Medical Sciences (UAMS). A
single copy of these materials may be
reprinted for noncommercial personal use
only. “UAMS,” “UAMS Online,” “UAMS Today,”
“UAMS Update,” “uams.edu,” and “Here’s to
Your Health” are marks of UAMS. |
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