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Aug. 25, 2005 -- The widely touted benefits of homeopathic drugs are merely placebo effects, a new study suggests.
Clinical trials almost always show that patients given inactive sugar pills -- placebos -- do better than untreated patients. It's called the placebo effect.
Clinical trials of homeopathic remedies sometimes show that these treatments work better than placebos. But a new analysis -- comparing published studies of homeopathic drugs to matched, randomly selected studies of medical drugs -- suggests that these apparent homeopathic drug effects are merely placebo effects.
Matthias Egger, MD, director of the department of social and preventive medicine (ISPM) at the University of Berne, Switzerland, led the study. He notes that small studies of both homeopathic and medical drugs are prey to biases favoring positive results. Such studies, he says, show relatively large positive effects for both homeopathic and conventional medicines.
But larger, more careful studies have fewer biases, Egger says. And these studies tell a different story.
"The effect of homeopathy disappears if you look only at large, good trials; whereas the conventional medicines' effect is still there," Egger tells WebMD. "This means there is no difference between placebo and homeopathic remedies."
Egger and colleagues report their findings in the Aug. 27 issue of The Lancet.
What is Homeopathy ?
Homeopathy is based on what its practitioners call the law of similars. The idea is that if a person has a symptom - such as a fever - it is the body's way of trying to kill off a germ. So a person would be given a medicine to help this symptom along: in this case, something that causes fever.
However, homeopathic medicines use only a very, very tiny amount of any medicine. An active ingredient is diluted, shaken, and diluted again. This is done so many times that few if any molecules of the original agent remain in the medicine. The idea is that the essence of the active ingredient is imparted to the medicine.
Homeopathic Doctors Cry Foul
Clinical trials may be biased, but not more than the Egger study, says homeopathic doctor Joyce Frye, DO, MBA, president of the American Institute of Homeopathy and a researcher at the University of Pennsylvania, Philadelphia.
"It is a flawed study. It starts out with a bias that the authors clearly state -- an assumption that the beneficial effects seen in clinical trials of homeopathy are probably from biases," Frye tells WebMD. "They base their conclusion on the restriction of their analysis to only a few trials -- eight trials of homeopathy with six trials of conventional medicine. Those numbers are too small for scientific comparison."
What really irks Frye and other doctors of homeopathy, however, is that homeopathic remedies are not supposed to be used like medical drugs.
"We are trying to treat the individual rather than the disease," Frye says. "Only 16% of these clinical trials looked at classical homeopathy as it is practiced. When we do clinical trials, we try to make them look like traditional medicine trials, but the reality is that is not where homeopathy excels. The more we try to fit the framework of traditional medicine, the more we are flawed in studying the way homeopathy is actually delivered."
For example, Frye says, homeopathy expert and University of Arizona researcher Iris Bell, MD, PhD, recently studied homeopathic treatment of fibromyalgia. Bell's team treated about 60 patients but used some 40 different medicines, Frye says.
"Homeopathy is not one medicine for one disease, but medicine that matches the totality of symptoms a patient has," she notes.
Where's the Medicine?
The thing about homeopathy that drives most scientists to distraction is the dilution theory behind homeopathic medicines. The medicines are made by taking a substance and diluting it again and again -- often until not one molecule of the substance remains in the final medicine.
The idea, according to material scientist Rustum Roy, PhD, of Penn State University, is that this changes the structure of the water in which the active substance is diluted.
"It is a fact that the structure of water and therefore the informational content of water can be altered in infinite ways," Roy says in a news release from the National Center for Homeopathy.
But other researchers find such arguments absurd.
In an editorial accompanying the Egger study, Jan P. Vandenbroucke, MD, PhD, professor of clinical epidemiology, Leiden University Medical Center, Netherlands, notes that objections to the theory go back to 1846. It was then that British researcher John Forbes said that the idea of a medicine getting stronger the more it is diluted is "an outrage to human reason."
"I do not know what it is about the dilution theory that attracts people to it. I really do not know," Vandenbroucke tells WebMD. "But somehow the appeal has been consistent for 150 years."
What Doctors Can Learn From Homeopathy
Given his study, it is surprising to learn that Eggers thinks people get a real benefit from seeing homeopathic doctors.
"Homeopathy is difficult to reconcile with basic scientific principles," Eggers says. "But the clinical literature is compatible with the notion that people treated with homeopathy do feel better."
Eggers explains that his study casts serious doubt on whether homeopathic medicines have specific effects.
But there's more to homeopathy than drugs, he says.
"Perhaps the positive effect is due to the wider experience of meeting someone who is very interested in you, who takes a very detailed history that no conventional doctor would do," Eggers says. "It is the whole experience of this holistic system. I am not surprised when people get better and share these beliefs. But is it something in that little white pill, or is it something in the relationship and the process of seeing a homeopathic practitioner?"
The advantage homeopathy and other alternative therapies have over traditional medicine, Vandenbroucke says, is that practitioners of these treatments spend more time with people than doctors are able to do.
"Even if people give you the wrong explanation about what you seek treatment for, the fact that they spend a long time speaking with you might help," Vandenbroucke suggests. "This does not mean the principle behind homeopathy works. And the tendency of many medical doctors to say, 'Well, it won't do harm, and if the patients like it, let's do it' -- this is intellectually dishonest. Because patients have a right to know if a medicine really works or not."
If the context of homeopathy works -- but not homeopathic medicine -- then doctors have a lot to learn.
On the other hand, just buying homeopathic remedies at your local drug store -- where they are available without prescription -- is a bad idea.
"My message to patients is clear and simple," Vandenbroucke says. "As a drug principle, homeopathy just doesn't work. That does not mean that if people talk with you for a long time, and are concerned about you, you won't feel better. But just going to the pharmacy and buying it does not work."
Frye, too, has advice for patients. She speaks as a patient as well as a practitioner -- homeopathy, she says, once saved her son from a life-threatening illness.
"Homeopathy it is worth exploring to see if it can help, regardless of what the naysayers say," Fry says. "It is about treating patients, not about doing studies. Although we would love to do big studies if anybody was out there wiling to fund them."
SOURCES: Shang, A. The Lancet, Aug. 27, 2005; vol 366: pp 726-732. Vandenbroucke, J.P. The Lancet, Aug. 27, 2005; vol 366: pp 691-692. News release, National Center for Homeopathy. Matthias Egger, MD, director, department of social and preventive medicine, University of Berne, Switzerland. Jan P. Vandenbroucke, MD, PhD, professor of clinical epidemiology, Leiden University Medical Center, Netherlands. Joyce Frye, DO, MBA, president, American Institute of Homeopathy and postdoctoral research fellow, center for clinical epidemiology and biostatistics, University of Pennsylvania, Philadelphia.