順勢療法效用被過度誇大？
摘錄自：天下雜誌 經濟學人電子報 2014/4/11
2014-04-03 Web
only 作者：經濟學人
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| 圖片來源：flickr.com/photos/epsos/ |
在任何一間健康養生商店，你都有機會看見一盒又一盒的順勢療法藥品；它們聲稱可以治療各種困擾你的病症，但翻到包裝背面之後，上頭寫的成份也許會讓你十分疑惑。它們可能含有輾碎的蜜峰、蕁麻甚至是砒霜，以及乳糖、蔗糖等糖份。美國人一年花費約30億美元購買順勢療法藥品，他們到底在想什麼？
順勢療法的歷史可追溯至18世紀末。德國醫生哈尼曼（Samuel
Hahnemann）並不信任當代醫學；當時，醫生會利用水蛭放血、用熱灰泥帶出水泡，哈尼曼的質疑當然有其合理性。1790年，一次發燒改變了哈尼曼的職涯。他在吃下金雞納樹皮磨成的粉之後，發現自己的體溫升高。金雞納樹皮含有奎寧，當時已知奎寧可以治療瘧疾。哈尼曼思考著眼前的事實：金雞納樹似乎會讓他發燒，發燒是瘧疾的癥狀之一，金雞納又能治療瘧疾。他用十分跳躍的邏輯做出結論：會在健康之人身上造成某種癥狀的藥物，就能用來治療會產生這種癥狀的疾病。
哈尼曼認為，藥物成份應該重覆稀釋和搖動，此過程稱作「增益」。他相信，療效成份的含量越小，藥物的效果就越強。順勢療法藥品使用各種術語描述其效果；其中一種常見的描述方式是「NC」，C代表成份以1:100稀釋，N則為稀釋的次數，因此，200C表示1公克的成份以100公克的水稀釋，並重覆此過程200次，如此稀釋之下，原始成份已完全消失。多數順勢療法藥丸完全是以糖份製成，然而，藥丸理當保有原始成份的「記憶」。
這實在難以令人信服。美國國家衛生研究院指出，研究順勢療法相當困難，因為在藥品只含極少量、或完全不含療效成份的情況下，實在難以檢驗其效果。最完整的順勢療法研究於2005年出版，其結論為「沒有明確證據」可以證明順勢療法的效果優於安慰藥；而在類似試驗中，傳統藥物則展現了特定的臨床效果。正如國家衛生研究院所說：「順勢療法的部分關鍵概念，與化學和醫學的基本概念不符。」（黃維德編譯）
©The Economist
Newspaper Limited 2014
The Economist
The Economist explains
Why homeopathy is nonsense
By The Economist
From The Economist
Published: April 03, 2014
Apr 1st 2014,
23:50 by C.H. | NEW YORK
VISIT any health
shop and you are likely to see them: packages of homeopathic remedies claiming
to cure whatever ails you, from coughs and fever to insomnia and asthma. Flip
the package of medicine, however, and you may be confused by the listed
ingredients. Some claim to contain crushed bees, stinging nettles and even
arsenic, as well as sugars such as lactose and sucrose. Americans spend some $3
billion a year on homeopathic medicines. What are they thinking?
The history of
homeopathy—literally, "similar suffering"—dates to the late 18th
century. Samuel Hahnemann, a German doctor, was unimpressed by contemporary
medicine, with good reason. Doctors used leeches to let blood and hot plasters
to bring on blisters, which were then drained. In 1790 Hahnemann developed a
fever that transformed his career. After swallowing powder from the bark of a
cinchona tree, he saw his temperature rise. Cinchona bark contains quinine,
which was already known to treat malaria. Hahnemann considered the facts:
cinchona seemed to give him a fever; fever is a symptom of malaria; and
cinchona treats malaria. He then made an acrobatic leap of logic: medicines
bring on the same symptoms in healthy people as they cure in sick ones. Find a
substance that induces an illness and it might treat that illness in another.
Hahnemann then
decided that ingredients should be diluted and shaken repeatedly, a process
called "potentiation". The smaller the amount of the active
ingredient, the more powerful the medicine would become, he believed.
Homeopathic remedies use various bits of terminology to convey their supposedly
potency. One common designation is "NC", where C signifies that a
substance is diluted by a ratio of 1:100 and N stands for the number of times
the substance has been diluted. So a dilution of 200C would mean that one gram
of a substance had been diluted within 100 grams of water, with the process
repeated 200 times. At this dilution not a single molecule of the original
substance remains. Most homeopathic pills are made entirely of sugar. However,
the pills are supposed to retain a "memory" of the original
substance.
This is bunk.
Studying homeopathy is difficult, points out the world's biggest funder of
medical research, America's National Institutes of Health (NIH), because it is
hard to examine the effects of a medicine when that medicine has little or no
active ingredient. Researchers can neither confirm that the medicine contains
what it claims to nor show the chemical effect of the diluted medicine within
the body. The most comprehensive review of homeopathy was published in 2005 in
the Lancet, a medical journal. Researchers compared trials of homeopathic and
conventional medicines. In the bigger, well-designed trials, there was "no
convincing evidence" that homeopathy was more effective than a placebo,
they found. Meanwhile, in similar trials of conventional drugs, medicines
showed specific clinical effects. As the NIH dryly notes: "several key
concepts of homeopathy are inconsistent with fundamental concepts of chemistry
and physics."
©The Economist
Newspaper Limited 2014
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