American Botanical Council Reviews Ephedra Safety
31 March 2003
by Wyn Snow, Managing Editor
Ignorance
of scientific information can be the greatest danger faced by anyone
taking supplements.
According
to Dr. Joshua Perper, Broward County's medical examiner, several
medical conditions as well as ephedra intake contributed to Oriole
pitcher Steve Bechler's recent death from heat stroke. Bechler was
taking 150% percent of the manufacturer's recommended intake level
(three pills instead of two). Did Bechler also ignore label warnings
that people with heart conditions and high blood pressure should
not take this supplement?
By
and large, most supplement labels contain very little information
about safety or contraindications or drug interactionsand
while most herbs enjoy a remarkably good safety record, both contraindications
and interactions with drugs and/or foods do occur. Recently, the
American Botanical Council (ABC) developed a safety labeling program
that will help manufacturers put reliable and comprehensive safety
information where it is needed most: on the label and in the hands
of consumers.
This
label information is based on scientific monographs akin to those
developed by the FDA for 0ver-the-counter drugs. Among the 29 monographs
covering popular herbs in ABC's new book, The ABC Clinical Guide
to Herbs, is one for ephedra. Here are some highlights:
What
is a safe dosage level?
The
recommended maximum daily intake for an adult is 100 mg of total
ephedra alkaloids. (This is from the US herb industry labeling policy
that has been adopted as law in several states.)
Dosage
levels of 30 mg of total alkaloids per dose, and 90 mg of total
alkaloids per day have shown no observed adverse effects. The lowest
level where adverse effects are observed is 150 mg/day. (This is
based on the Cantox toxicological review.)
What
does ephedra do to the body?
The
alkaloids in ephedra stimulate the nervous system in a way that
increases heart rate and causes blood vessels to constrict (become
narrower). This also causes blood pressure to rise.
Herbal
preparations of ephedra also enlarge bronchial passages (which makes
it useful for asthma), induce perspiration and increase urine production
(diuretic).
Ephedra's
use as an aid to weight-loss is due to its thermogenic (literally
"heat-making") effects on metabolism, inducing an obese body to
burn more fuel than it otherwise would. This effect is raised when
one combines ephedrine with caffeine. However, it should be noted
that caffeine stimulates the nervous system in ways quite similar
to ephedra (heart rate, blood vessels, etc).
Ephedrine
also lengthens the time a meal stays in the stomach, which may help
reduce the amount of food eaten.
Decades
of widespread use have shown no indication of addiction to ephedra.
There
is some evidence that initial increases in pulse rate, blood pressure
and serum glucose levels disappear with chronic use over a period
of 4-12 weeks.
Side
effects
Adverse
effects of ephedra are known to include insomnia, motor restlessness,
irritability, headaches, nausea, vomiting, disturbances of urination,
and tachycardia (fast heart beat). The German Commission E (which
was Germany's regulatory body governing herbs) indicated that doses
higher than 300 mg/day of total ephedra alkaloids "may produce a
drastic increase in blood pressure [and] cardiac arrhythmia."
In
reports to the FDA of adverse events that may have been caused by
ephedra, the most frequently reported symptom was hypertension,
then palpitations or tachycardia or both. Stroke and seizures followed
in the chronology of adverse events, some of which resulted in death
or disability.
However,
the rate of occurrence of heart attacks and strokes among people
who use ephedra seems to be no different from that in the general
population.
Drug
interactions
Information
on drug interactions is based on the synthetically derived alkaloids
of ephedrine and pseudoephedrine. Thus, while this information
probably applies to the herbal form of ephedra, there is no
specific research on herbal ephedra drug interactions.
Ephedra
use might affect antihypertensive drugs (including ACE inhibitors
and beta-blockers), bromocriptine, and sympathomimetics.
Ephedrine
and/or pseudoephedrine definitely interact with
- cardiac
glycosides or halothane
- corticosteroids
- guanethidine
- MAO
inhibitors
- methyl
xanthines (caffeine, theophylline)
- secale
alkaloid derivates or oxytocin
- urinary
alkalizers (eg, acetazolamide, sodium bicarbonate)
Who
should not take ephedra?
The
German Commission E noted that people with the following medical
conditions should not take ephedra:
- anxiety
and restlessness
- hypertension
- glaucoma
- impaired
circulation of the cerebrum
- adenoma
of the prostate with residual urine accumulation
- pheochromocytoma
- thyrotoxicosis
Additional
contraindications published in Brinker's Herb Contraindications
and Drug Interactions (Eclectic Medical Publications, 2001)
include:
- pregnancy
- anorexia
- diabetes
- heart
disease
- insomnia
- stomach
ulcers
- renal
failure
- children
The
American Herbal Products Association (AHPA) also states that ephedra
should not be used during pregnancy or while nursing, by anorexics
or bulimics, or by people with glaucoma. AHPA also warns against
excessive or long-term use, and says ephedra may act as a thyroid
stimulant and may potentiate MAO inhibitors.
History
and controversy
The
ABC ephedra monograph devotes three pages to the history and background
of ephedra usewhich began in China thousands of years ago.
Used for treating asthma, colds and flu, cough, wheezing, nasal
congestion and a few other conditions, ephedra (ma huang)
appears in China's oldest listing of therapeutic herbal agents.
The herb itself is still in the official government formularies
for medical use in China, Germany and Japanalthough most other
countries use synthetic forms of ephedra's two main chemical compounds
instead (ephedrine and pseudoephedrine).
Controversy
over ephedra's safety began in the 1980s and 90s when ephedra was
incorporated into supplements designed to aid weight-loss. In 1994,
the American Herbal Products Association (AHPA) and the National
Nutritional Foods Association (NNFA)which are two of the major
trade organizations for the supplement industrycreated a labeling
policy for its members concerning daily intake limits and contraindications.
This labeling policy has since been adopted by all of the herbal
industry trade associations (see our page: Ephedra: Guidelines For
Dosage And Label Warnings).
The
American Medical Association (AMA) takes a very different viewthat
all ephedrine substances (including ephedra) should be restricted
to prescription use only, and eliminated from foods, OTC drugs,
and dietary supplements.
In
1996, Ohio was the first state to adopt a law that requires all
ephedra product labels to carry the AHPA/NNFA safety guidelines.
Hawaii, Michigan, Washington, Oklahoma and Nebraska have followed
suit.
During
the 1990s, the FDA received approximately 800 adverse event reports
on ephedra from a variety of sources. In 1997, the FDA sought to
use these reports as the basis for highly restrictive daily intake
limits. However, their proposal was criticized by scientific and
medical experts as well as by industry and consumers as being both
too restrictive and not scientifically based. The US General Accounting
Office (GAO) agreed, and the FDA withdrew its proposed regulation.
In
2000, the Office of Women's Health, part of the US Department of
Health and Human Services, held a two-day public hearing on the
safety of ephedra. Two points of view emerged from the testimony
of scientific and medical experts.
The
Ephedra Education Council, an industry-based group, presented a
review of both the published literature on ephedra safety and on
the FDA's collection of 1000 adverse event reports. This review
concluded there was no evidence of an association between ephedra
and serious adverse events at the industry-recommended levels of
intake. It also criticized an analysis of 1000 adverse event reports
that was conducted by FDA consultants and subsequently published
in the New England Journal of Medicine.
An
FDA-sponsored review of 140 of the events reported to its MedWatch
program concluded that one-third were "probably" and another third
were "possibly" associated with ephedra. These included 17 reports
of hypertension, 13 reports of palpitations and/or tachycardia,
10 reports of stroke, and 7 reports of seizures. Of these, 10 resulted
in death and another 13 in disability.
The
Ephedra Education Council also presented the results of the first
comparison of how often heart attacks, strokes and seizures occur
in the general population and among ephedra users, discovering no
evidence of increased risk.
The
Office of Women's Health issued a report that recommended further
research, a recommendation echoed by other experts and agencies
investigating ephedra safety.
In
2001, a researcher concluded, "The peer-reviewed scientific literature
suggests that the risks of caffeine and ephedra are outweighed by
the benefits of achieving and maintaining a healthy weight. Confirmation
of that conclusion for herbal products containing caffeine and ephedrine
awaits controlled clinical trials."
And
in 2002, the Secretary of the Department of Health and Human Services
called for more research on ephedra to determine its safety and
efficacy.
The
ABC overview of ephedra's history concludes with this statement:
"Supporters
and some prominent critics of ephedra agree that scientific reviews
of the cases of the adverse event reports on ephedra do not establish
causality, thereby making additional clinical research the key to
developing regulatory policy."
Source
American
Botanical Council. "Ephedra." The ABC Clinical Guide to Herbs,
2003, pages 110-121. See www.herbalgram.org/default.asp?c=guideephedra.
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