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March 7, 2000 (San Diego) -- Once scoffed at by doctors and mainstream scientists, alternative medicines may actually have benefits that can be demonstrated in valid laboratory experiments, according to data presented at a conference of allergy and asthma experts here. However, other studies presented here reveal dangerous side effects of these products.
"Given the [reputation for effectiveness], low cost, and relative absence of side effects, the use of traditional Chinese medicines has been growing in Western countries in the past few years," says Xiu-Min Li, MD, of the Mount Sinai School of Medicine in New York. However, she says, not much data exist to confirm or refute the claims that have been made for Chinese medicines.
To study the effects of these herbal remedies on asthma, Li and colleagues at Mount Sinai and the Johns Hopkins University School of Public Health in Baltimore developed a mixture, referred to as MTSD, based on a popular Chinese remedy. Their formula was slightly modified from the normal preparation. They tested the formula in mice with asthma and compared it with another Chinese medicine, ding-chan tang (DCT), and to dexamethasone, a potent steroid drug sometimes used in the treatment of asthma.
MTSD proved as effective as dexamethasone at reducing the lung's extreme sensitivity to substances that provoked asthma attacks in the mice. DCT also had some effect, but not as much as the other two. MTSD also significantly reduced lung inflammation and mucus accumulation, which, says Li, can make a severe asthma attack fatal.
She and her colleagues also found that while dexamethasone suppressed the immune system, MTSD had a better, more selective effect. "Our results suggest that may have some therapeutic effect in the treatment of allergic asthma," she says. "This herbal formula may be a good alternative approach."
But alternative remedies must be taken with caution, warns Raymond J. Mullins, MB, of the John James Medical Centre in Deakin, Australia. He says people with allergies could have serious, even fatal reactions to echinacea.
After two of his patients suffered severe allergic and asthma attacks within 20 minutes of taking echinacea products, Mullins reviewed a database on adverse drug reactions reported by Australia's doctors and pharmacists. During the 1990s, the database received over 400 reports of herbal products, including 44 involving echinacea. More than half of those cases were allergic reactions, most in patients known to be allergic to other substances. Symptoms included hives, swelling, and shock. Four patients required hospitalization.
Echinacea is a flowering plant related to the daisy and ragweed, Mullins says. It might provoke asthma or an allergic reaction in people who are allergic to components common to all of those plants. Echinacea's popularity Down Under has exploded in recent years, due to reports that "it may stimulate white blood cells to gobble up germs more effectively." Mullins warns that such claims are based on statements taken out of context from scientific papers.
Nevertheless, Australians take an estimated 200 million doses of it annually. Reactions to echinacea account for more than 10% of the adverse reports involving alternative medicine in Australia. But this could be an underestimate, says Mullins, because "minor reactions such as transient rashes or worsening of underlying asthma are likely to go unnoticed and unreported."
"We need to challenge the concept that natural means safe," he says. "Herbal medicines have not been examined carefully for risks. If you have allergies, including asthma, eczema, and hay fever, I recommend that you don't take echinacea at all."
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