Of course, there are medicinal herbs in the West as well as those from China that contain poisonous substances. But even Paracelsus said that the dose makes the poison, and presumably other doctors said the same centuries before. However, if the specialist in traditional Chinese medicine (TCM) has learnt their trade, no incidents should occur.
The incident with the women who attended a slimming clinic in Belgium, where a miracle cure for obesity was advertised, regularly appears in the newspapers. As it turned out, however, in addition to two Chinese herbs, this mixture contained several chemical drugs, e.g. an amphetamine derivative. In drug circles, amphetamines go by the name of speed. The Chinese herbs were held responsible for the damage to the unfortunate women. They fell ill with kidney failure and had to undergo dialysis or a kidney transplant or even kidney cancer. Around fifty women suffered this sad fate over a short period of time. For years, or in the meantime decades, there has been discussion as to why this could have happened. The suspected herbs have been used in China for more than a hundred years without such an accumulation of damage becoming known. Although it was discovered that Aristolochia (Guang Fang Ji) was mistakenly used instead of the intended herb Stephania (Han Fang Ji), this still does not explain the mass of cases. Aristolochia is indeed a poisonous herb. It contains aristolochic acids, which have a toxic effect. In this clinic, it must be assumed that the combination of Western medicines with this aristolochia led to a fatal build-up of toxicity. Since then, plants containing aristolochic acid have been banned, first in Europe and then in China. If you read old herbal books, the healing effect of the Easter lily (Aristolochia clematidis) known in Europe is praised. Hazel root, a species of asarum native to our country, also from the Aristolochiaceae family, was also used medicinally in the past and is therefore also banned. A type of asarum is also used in TCM. It has been, it has to be said, because its use is prohibited here for the above reasons. When used correctly, the aristolochic acid content is so low that it sometimes falls below the detection limit despite the use of highly sensitive laboratory equipment. But a ban is still a ban. Many TCM specialists miss this herb very much. It is indispensable for certain diseases. There is no substitute for another plant, at least none with comparable healing powers in cases where its use would be necessary.
Asarum europaeum
You may have another example in mind of a medicinal herb that was recently labelled as poisonous: coltsfoot, a proven and highly valued herb for coughs for centuries. Druggists and pharmacists rebelled, but the herb could not be saved. Among other things, it contains so-called pyrrolizidine alkaloids (PA). These do not appear to have any benefit. The medicinal healing effect of coltsfoot is based on other substances that are also contained in this herb. Pyrrolizidine alkaloids can cause liver damage in higher doses, for example, or they can promote the development of cancer. This has been seen in cows grazing on meadows where pyrrolizidine alkaloids grew in large quantities. Today, herbs may only contain such substances in minute quantities by official regulation in order to be used medicinally. However, this means that the desired quantities of useful substances cannot be achieved and they are not used. Using a chemical process, it should be possible to filter out the pyrrolizidine alkaloids. According to reports, a well-known Swiss manufacturer of a butterbur gel does this. And by means of selection, coltsfoot plants low in pyrrolizidine alkaloids can allegedly be bred.
Many other plants also contain PA, e.g. water eupatorium (Eupatorium). Greiskraut (Senecio), butterbur (Petasites), comfrey (Symphytum). PA form plants to protect themselves from predators.
Huflattichblüten
Scientists love to search our plants for active ingredients. They find this and that and isolate these substances. Then they test them on mice, animals and humans and get an idea of their effects. But what is their goal? They often want to find out, in the service of the pharmaceutical industry, whether these substances can be used to produce a medicine that sells well. However, pharmaceutical chemistry works with fairly simple methods in the laboratory. At most, it can analyse a single substance at a time. A whole plant would be far too complicated. A plant is a huge factory in which substances are constantly being produced and exchanged. This factory is incredibly flexible in the range of its products. The palette changes day and night, summer and winter, at the time of germination and at the time of ripening. Tens of thousands of different chemical compounds flit around. Even when the plant is harvested, cut off, dead so to speak, the factory continues to work. The herb continues to change during the storage period. And scientists often only extract a single substance from it, for example caffeine from coffee. As humans are equally a wondrous factory that reacts to external influences in many more complicated ways than a plant, we are amazed when one person is wide awake after drinking caffeine and another can lie down and fall asleep calmly after ten cups. Our simplistic and simplistic laboratory models never get to the heart of real life. Why does one person and not the other get an itchy rash from an antibiotic, another gets diarrhoea and the third severe fatigue, the fourth a vaginal fungus and the next vomiting? And why is it that nobody can say in advance who will experience this or that after taking an antibiotic? These are questions to which medicine, which calls itself scientific, has hardly found any answers.
This is also the case with the toxicity of medicinal herbs. There are clearly poisonous herbs where we can say quite precisely that this or that will happen after taking so and so many grams. But there is no need to talk about these herbs. Everything is more or less clear. We will have to limit ourselves to the right dose while maintaining a certain safety margin.
The ancient Chinese discovered long ago that there are herbs in nature that work very well against a certain disease, but unfortunately have toxic side effects when left pure. They therefore developed methods of retaining the effective substances in the plant and rendering the unnecessary, toxic ones harmless. Complicated procedures were developed, for example repeated boiling with the addition of vinegar or wine or minerals such as gypsum and lime, by burying in the ground, by storing in containers made of certain materials, by boiling together with other herbs. Such methods are still used today and everyone knows how to test herbs treated in this way and how to use them. Moreover, it is never the case that a Chinese herb is used alone. It is always in the company of others. Such formulations have been weighed out and administered in exactly the same dose down to the gram for centuries, in some cases for two millennia. In such formulations, it happens that certain herbs potentiate a desired effect and neutralise an undesired one. There is an incredible wealth of experience behind this. So when a quack comes along and mixes chemical substances with Chinese herbs, it is no wonder that nothing sensible, or worse, as in the case of the women in Belgium, something fatal comes out of it.
Fingerhut (Digitalis)
It is somewhat more complicated when the healing effect of a herb is based on the presence of the poisonous ingredient and a certain quantity of it is required and when the therapeutic dose is close to the toxic dose. In conventional medicine, digoxin, a poison from the foxglove (digitalis), was used for decades to treat heart failure. The therapeutic range was very narrow. That also exists. I know the case of a woman who suffered from a rheumatic disease. Initially, the herbs didn't help her much because the dose was low. But as the amount increased, the formula took effect. The rheumatism, polymyalgia rheumatica, disappeared and has not returned for many years. The recipe contained aconite, which is said to be the most poisonous plant in the northern hemisphere. The ancient Chinese had already known how to utilise its healing properties centuries ago. By cooking it for a long time together with other herbs, they were able to minimise the toxic aconitine content and absorb its toxicity with the ingredients of other herbs, e.g. ginger.
Eisenhut, Aconitum napellus, das europäische Pendant zum chinesischen Aconitum carmichaeli
Aconite is an integral part of some classical schools of TCM. Students of the so-called fire school rely on it to a large extent.
Our western scientists, as described above, start from isolated individual substances. It is too complicated for them to have to explain what happens when the whole plant is consumed rather than the individual substance. In fact, substances have been found which, when fed individually to mice, caused cancer in them. However, when given the whole plant, the mice were actually better protected against cancer than a normal population of mice that were given neither this nor that. This is incredibly difficult for scientists to explain. That's why they don't like such tasks. But for a Chinese doctor, this is the clearest thing in the world, completely logical. If you also have an answer ready here, then you are well on the way to having internalised important principles of the Chinese way of looking at things. Of course, this is not just Chinese thinking. You would simply think that this is common sense. After all, it can't have just been invented in China. To summarise, we must not accept a priori that someone comes along and says that this or that plant is poisonous because it contains this or that chemical substance. We must be allowed to respond immediately with 'Yes, but...'. We are allowed to question such claims and ask about their origin. We then often come to the conclusion that such statements should not be left unchallenged. Otherwise we run the risk of having a whole heap of medicinal herbs taken away from us bit by bit.
Have you ever read the package leaflet of a chemical medicine? The wildest side effects are accepted and thrown onto the market with the blessing of the authorities. Even deaths are accepted without anyone thinking of banning the drug. The most recent example is Viagra. The Weltwoche of 3 September 1998 reports that 123 men have already died from it. The next one will probably be thalidomide (thalidomide). The chemical industry is expecting huge profits from it. It should be authorised soon. And this brings us to the point where we need to talk about toxicity: if plants had as big a lobby as the chemical industry, it would not be possible to push them further and further into a corner. This is not about saying that chemicals are bad and plants are good. Both can achieve great things at the crucial moment. Chemistry and herbal medicine both draw from a pool of resources that should be cherished and nurtured. It is hard to see why it is necessary to denigrate and compete with each other. The matter should be discussed objectively and not simply left to a market that only sees profit.
At Complemedis, we have done a lot of work on issues relating to the toxicity of herbs and have built up a large database. We are already providing advice to authorities, scientists from East and West, therapists and interested parties.
Severin Bühlmann
25.11.2004, revised 2022
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