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<Home> <Health an Islamic Perspective> <Islamic Medicine> <Prospects> < The Role of Herbal Remedies as an Alternative to Modern Drug Therapy> THE
ROLE OF HERBAL REMEDIES AS AN ALTERNATIVE TO Dr. Simon Y. Mills ENGLAND PREAMBLE The practitioner of herbal medicine in the modern world has few ways in which to present his arguments for the advantages of his chosen therapy to the scientific and medical community. There are several reasons for this. It is inherently difficult to analyse, quantify or predict the exact pharmacological action of an agent that is both chemically extremely complex and highly variable as between samples. There is in fact very little doubt that even the attempt to accomplish this in order to gain complete scientific 'respectability' for herbal medicine is doomed to failure. An equally difficult problem in communication is provided by the insistence of the serious herbal practitioner that the aims of the therapy must be qualitatively distinct from those of modern western medicine. This is a point ignored in most popular accounts of herbalism in the west and deserves a little elaboration here. It is central abiding principle in the professional practice of herbal therapy that the patient manifests uniquely a will to live, a life force, an unquantifiable and astonishing ability to grow, prosper and thrive, to transform environmental stresses in to health in the positive sense of that word. This means that the practitioner accepts that there is already present a will and ability recover from setbacks and disease, a 'vis medicatrix naturae' as Hippocrates put it, and that it is therefore the practitioner's obligation to aid the natural healing process when this is obstructed. The process of disease is seen, not as something to be arbitrarily removed by direct antagonists to the pathological process as visualized in modern 'allpathic' therapy, but as a manifestation of thwarted recovery process. The symptom is seen, literally, as a 'signpost', to be read as part of an attemept to locate the nature of the obstruction, to assess the needs of the underlying vital functions. Herbal remedies are then seen as essentially supportive of these functions, and it is considered that an evaluation of their potential as healing agents must be bound to this fact. The herbal practitioner therefore resists the facile listing of herbal remedies as effective for ameliorating arbitrary pathologies. Much more important to him is to understand something of the physiological activity of a remedy than to be told that it is good for arthritis or asthma or whatever. Each patient is considered as a unique case, to be treated most likely with a unique formulation of remedies independent of the pathology he or she might be labeled with. All this means that the parameters by which a herbalist finds a remedy valuable are often quite distinct from those current in scientific medical thought. Evidence of validated antipathological activity is genuinely less important to the herbal practitioner than the day-to-day experience of its efficacy in the personal encounter. The value of any scientific findings is seem more as a potential elaboration of a total view of the remedy's activity in the physiological realm than as a binding definition of its actions and limitations. Much more could be said of the implications of this viewpoint, of the different view of the effects of treatment and its course in time, of the new light cast on the concept of the 'side-effect', and of the accomodation that the herbalist finds possible with the pharmacological complexity and variability of the materia medica. However, that is the province of a more philosophical treatise. The purpose of this article is to demostrate by means of example how the evidence that does exist for a few individual remedies can be assembled to make a case for their vitalistic application in the manner briefly described. In the presentation of what analytical and experimental evidence does exist information will have been called from a very wide variety of sources. To reduce the opacity of this paper accredition will not be made for absolutely every analytical statement. Rather there will be appended a general literature list from which the bulk of the detail has been obtained. Specific literature citations will be restricted to the most notable claims in the text. The author will be pleased to provide any reader with detailed sources for any other item that interests him particularly. The restriction in citations will be particularly apparent in the lists of constituents for each remedy and in the more widely accepted pharmacological activities. Crataegus monogyna (Jaeq) This is one species of a pair that is found widely throughout Europe that is for medicinal purposes taken together (the other more temperate species being C. Oxycantha). C. monogyna is found in Europe and around the Mediterranean regions into north and West Asia. It is a shrubby tree found commonly in hedgerows in cultivated areas with corymbs of small white or pink flowers giving way to red berries in the autumn. The leaves are lobed and stipulate. Throughout Europe, Crataegus has earned a reputation as a useful remedy for disorders of the heart and for dropsy; its use for coronary and circulatory difficulties is a more recent phenomenon than other long-established usages but this perhaps reflects the increasing understanding of heart function in the last century. However, it is now one of the prime remedies for treating a variety of cardiac problems in the European materia medica, appearing to have the ability to dilate the coronary vasculature whilst also having a bradycardic effect on heart rate. It finds equal applicability for angina and other coronary difficulties as for the treatment of arrythmias, especially where the latter have arisen from prior coronary disturbance. Beyound this there is apparantly a general vasodilatory effect that helps in the overall treatment of some cases of hypertension and in some of the circulatory problems consequent on arteriosclerosis (e.g. intermittent claudication). In brief, the modern herbal practitioner sees Crataegus as a superb heart 'food' and relaxant with a gentle but cumulative general vasodilatory effect as well. There is a considerabale body of experimental evidence to support these impressions. A list of constituents for the leaves, flowers and berries would include the following: Flavonoid glycosides (including, rutin, quercitrin) Triterpenoid saponins ('Crataegus lactone') Procyanidins Trimethylamine Condensed tannins (forming red phlobaphenes, insoluble complexes). It is well-known, following Szent-Gyorgy, that flavonoids have an observable effect on the vasculature, reducing capillary fragility (providing essential in vivo support for asscorbic acid), dilating coronary blood vessels, slowing the heart rate whilist increasing stroke volume. They would thus provide a fair explanation for the effects of Crataegus if they were not also widely found in many other plants and foodstuffs that do not exhibit these effects to any notable degree. Further support, however, is provided in the report that the pholbaphene fraction (i.e. deposited condensed tannin complexes) showed evidence of the prolonged vasodilatory effect on the coronary vessels, and in addition increased the amplitude of the heart's contraction and potentiated the effects of caffeine, adrenaline, adenosine and papaverine on coronary circulation. Increased vagal tone slowing heart rate is a fair conclusion from the known effects of the procyanidins (yielding cyanides on hydrolysis), and from the suggestion that the whole plant exhibits anticholinesterase activity. Perhaps the most active components may yet prove to be triterpenoid saponins. This class of plant constituents has only recently been investigated and has already been shown to be instrumental in the actions of Panax ginseng and Glycyrrhiza glabra (see below) for example. Most pertinent here is the work that has been done on the saponin fration of Aesculus hippocastanun that has shown that it is notable in the whole remedy's action in reducing oedema and benefiting varicosed veins. Whatever the pharmacological explanation however there are clinical records showing theability of tberries to reduce hypertension caused by both arterterioslerosis and renal damage, and the flowers to improve the health of heart patients troubled with mitral stenosis and progressive coronary occlusion. Other studies concluded that the remedy had a favourable effect in cardiac arrythmias, especially extrasystoles and paroxysmal tachcardia, and prevented ECG changes due to hypooxia. A reduction in digitalis dosage after treatment with Crataegus is a strong possiblity. No side effects have been reported during therapeutic use, toxic problems only arising with massive intravenous dosages or with non-theraputic doses administered chronically.
Allium sativum (L) This remedy has generated perhaps more scientific curiosity and research than any other plant not cultivated for supplies of allopathic drugs. It has through the ages accrued an almost phenomental reputation for helping a wide variety of conditions. It has moreover played a significant part in the diet of many countries. The main limitation to its use in European countries has been a strong social objection to the odour on the expired air of the taker, but there have been areas where this has bot been insurmountable and there is some applications. In general, the uses of garlic have fallen into two groups: the antimicrobial action it appears to possess, and the number of interrelated benefits it seems to have on the circulation. Of the two, it is the former that has been concentrated on in traditional herbalism ("a good preservation against infections". Prkinson, 1640, AD) whilst the use of garlic for circulatory problems, unusually, owes much to modern research findings for the plant. We shall look first at some known constituents: Volatile oil-allin, separated form enzyme a lliinase in intact plant; when crushed the two interact and allin is convenrted to allicin which is further oxidised to dially disulphide. Glucokinins Germanium Mucilage From an early stage it was clear that the volatile fraction, notably allicin was responsible for the unitbacterial action of Allium, it was found to be active in concentrations as small as 1:85,000. Clinical evidence for anitmicrobial activity has generally supported the traditional usage. Initial controlled trials to check the use since ancient times of Allium for leprosy were sufficiently encouraging for further testing to be recommended. It was found to perform commendably in the treatment of tuberculosis, and achieved a sound reputation in both World Wars in preventing sepsis and controlling suppuration. Some of the most interesting work has been done to investigate the potential of Allium sativum in normalizing bacterial populations in the gut: it has been one of the more common claims for the remedy by practitioners that it could check gut infections without destroying normal healthy flora. Some backing, if not explanation, for this assertion comes form Weiss, who reported a complete change in intestinal flora after Allium treatment, and from Marcovici who reported significant improvement in dysenteric diseases. Other clinical work has demonstrated relief in a number of gastro-intestinal disorders, including flatulence, vomiting, nausea, abdominal distension and dyspepsia. Given these findings, supported by herbal practitioners today, it is hard to avoid accepting that the action of Allium on the bacterial population of the gut is selective. Effects on the gut that are possible relevant to this activity include a general stimulation of digestive juices, and an increased absorption of thiamine from the intestine. There has also been observed a direct antimicrobial effect against staphylococci, streptococci, Escherischia typhosa, Bacterium dysenteriae, B. enteritidis, and Vibrio cholerae. At the early stage of research, the applicability of Allium to the treatment of cardiovascular disease was established. Marcovici was among many who suggested that the elimination of toxin absorption form the gut was central to this function, and this is a theme still taken up today. However, there is also clear evidence for direct effects on the circulation and vasculature; in reducing post-prandial blood cholesterol levels, and blood sugar levels-possibly involving the glucokinin constituents - as well as platelet aggregation, thromboxane synthesis and thus the tendency to thrombosis. Circumstantial evidence for the beneficial effect of Allium on the circulation comes from an examination of the statistics for heart disease in countries with or without a high consumption of garlic in the diet The traditional use of garlic for tumours is also supposrted by recent research. Enough in vitro and in vivo results have been forthcoming for one researcher to conclude that "it may lead to an effective therapeutic attack on the cancer problem". Japanese researchers have suggested that it is the presence of unusually high levels of the mineral germanium that is a vital feature in the antitumour activity. In total, there does seem ample backing for the herbal practitioner's view of Allium as an effective aid to the body in its attempts to come to terms with pathogens in its environment. Glycyrrhiza glabra (L) This is another plant whose traditional usage and modern potential have happily overlapped, with the latter being particularly notable. A brilliant survey of the subject has been conducted by Gibson and much of what follows is provided, along with full references, by him, with a minor contribution from other sources. In the past Glycyrrhiza has been used for its soothing and healing actions on the gastrointestinal tract and the respiratory system principally. There are incidental reputations for fever management and urinary disturbances as well. On examination, its constituents are found to include: Glycyrrhizing (salts of glycyrrhizic acid) Triterpenoid saponins Flavonoids Bitter principle (Glycyramarin) Asparagin Oestrogenous substances (including B-sitosterol) The key feature in the activity of the plant seems to be a steroidal fraction that includes the aglycone of glycyrrizin, glycyrrhetinic acid, and the near steroidal triterpenoid saponins. The similarity of these substances to steroidal hormones has helped to explain a number of hormonal effects in many medicinal plants. In Glycyrrhiza these effects are prominent. Thus it has been shown to have anti-inflammatory and anti-arthritic effects similar to hydrocortisone, to resemble the activity of ACTH in causing aidosterone-like retention of water and sodium, and loss of potassium at the kidney, increased blood pressure, and decreases in haemoglobin levels. It enhances the immunosuppressive action of cortisone, but on the other hand, inhibits its antigranulomatous action and its effects in increasing liver slycogen storage. The action of glycrrhetinic acid here is dependent on a functioning adrenal cortex: there appears to be a direct ACTH - like effect increasing adrenal production on the mineralocorticoids and androgens, but there is also an effect on reducing the breakdown of the corticoids at the liver and kidney. The effect can be dramatic: it has been reported that a woman with Addison's disease was maintained completely with an initial dose of 60g liquid extract of Glycyrrhiza per day, this dose being eventually reduced so that a maintenance dose of 3g daily was achieved. Whatever the full explanation of this effect proves to be it will also include the raising of serum levels of glutamicocaloacetic acid transaminase and glutamicpyruvic transaminase and thus the uncoupling of oxidative phosphorylation. The potential local actions of Glycyrriza are supported by the anti-inflammatory effects exhibited in treatment of corneal injuries and in cosmetics. There is further support for an inflammatory effect in the widespread allopathic use of Glycyrriza constituents for petic ulcers, though this is put largely to the ability of the remedy to promote an adherent film of protective mucus over the gastric wall, and possibly to reducing gastric acid secretions. Glycyrrhizin is found to increase bile secretion and the excretion of bilirubin and to have an antipyretic effect comparato sodium salicylate. Thevaried effects support the notion among modern herbal practitioners that Glycyrrhiza is well suited to providing benefit in any attempt to wean a subject off excessive administration of cortrisone or other steroids. It appears to have many of the relative advantages of ACTH with yet easy applicability by mouth. There is postulated the possible danger hypokalaemia and hypertension due to the mineralcorticoid effect if Glycyrrhizin is taken in large doses for an extensive period. This is no doubt a real risk but apart from glycyrrhizin the whole plant possesses diuretic components, notably asparagin and the flavonoids, that may diminish this effect. The application Glycyrrhiza to disorders of the respiratory system seems to be backed by its anti-inflammatory (and anti-allergenic) effects, with effects in tuberculosis comparable to deoxycortisones. There is also the reflex effect on the activity of bronchial muscle and the mucociliary escalator of all mucilaginous plants. Its traditional and clinical use for asthatic conditions and excessive coughing seems well supported here.
Cichorium intybus (L) This plant is chosen arbitarily as an example of one of the many 'bitter' remedies used throughout the world for their ability to stimulate the upper digestive system, increasing appetite, promoting the flow of digestive juices, and by increasing bile flow, 'cleansing the liver'. It has generally been accepted that the mechanism involves a reflex response to stimulation of the bitter taste receptors in the mouth (i.e. bitters are quite inactive when given by tube direct into the stomach). What has transformed the understanding of these bitter substances is the finding that the immediate result of stimulation of the bitter taste receptors is the release of the gastro-intestinal hormone gastrin. This in turn is known to increase gastric acid secretion (and thus the sterilizing stomach acid 'barrier' to gastrointestinal infection), increasing intestinal mobility, and increasing the secretion of bile and pancreatic juices. There is also an increase in salivary secretion (but not amylase). From these effects it is easy to project benefits for liver function especially in its detoxifying and eleminatory functions, and for the pancreas, including the endocrinal secretions linked as these are to the flow of pancreatic juices and thus explain in turn the apparent benefit that bitters have for disturbances in blood sugar levels. Gastrin is also active in increasing appetite and a general sense of well-being; with this and the undoubted benefits on digestion it is not surprising that bitters were for long considered superb general enhancers of vitality. Silybum marianum (L) This Mediterranean plant has been used in middle Europe for liver complaints for many years, the seeds being considered the active part. A protective effect on the liver has in fact been recently demonstrated, notably against the common experimental hepato-toxins carbon tetrachloride and phalloidine (from Amanita phalloides) and against chemically-induced cirrhosis. This protection lasted many hours after treatment. The conclusion drawn has been that the cell membranes of the hepatocytes have in fact been stabilized against the destructive effects of toxins. The main activity in the remedy has been conclusively associated with an unusual type of flavanoid-lignoid complex or flavolignan, in this case known as silymarin: this has been shown to enhance the activity of polymeraseA produced in the hepatocyte nucleolus so leading to increased ribosomal RNA activity and thus protein synthesis in the cell. It is this, with the membrane-stabilizing effect that is seen to explain not only the ability of the remedy to help protect toxicity, but to stimulate regeneration and repair as well. Vitex agnus-castus (L) It is one of the claims made for medicinal plants that they have an amphoteric or normalizing effect rather than a dynamic unilateral one. The actions of Vitex appear to be a good example of this. Its traditional use has been for disorders of the female reproductive system, with an almost contradictory list of indications (heavy menstruation and amenorrhoea for example) and including a notable effect in promoting lactation. In recent practice its applications have if anything been wider, forming the basis for treatments for all manner of menstual disorders, particularly premenstrual problems, menopausal symptoms, menorrhagia and dysmenorrhoea. The impression gained in usage has been that the remedy somehow normalizes the balance of sex hormones at different times of the month, with if anything a slightly progesteronal effect. Support for this has been provided by Probst and Roth who have shown that Vitex has effects similar to the corpusluteum on human subjects, established by histological investigation of the endometrium by curettage, by cytological examination of vaginal secretions, and by observing changes in basal body temperature. Further work with the oestrus cycle of rats showed the effect in shortening the oestrus only apparent in test animals already having abnormally frequent or lengthy cycles; from this and from clinical therapeutic results with patients it is summarised that the effect of the remedy is to normalize corpus luteum function, along with perhaps ovarian function in general, via the controling centres in the hypothalamus, rather than simply replacing corpus luteum hormone (there are no suitable steroidal compnents of the plant in anyn case). Confirmation of a significant effect on lactation has also been provided.
DISCUSSION A review of the available evidence for a number of herbal remedies is here presented. The remedies have been selected form a wide field and reflect the average state of affairs that pertains to the investigation of the better known remedies, although it must also be said that there are a great many remedies that have been barely examined experimentally in modern times. From what has been said at the beginning of this paper it will be apparent that the aim of assembling this information is to provide a modicum of independent support for the claims of herbal practitioner for their remedies, and incidentally reveal to a few that observable pharmacological activity is a property of herbal remedies (contrary to some allopathic pronouncements). The ultimate puspose of this paper, however, is to present the case for the use of herbal remedies as a valid healing therapy in the modern age. It is thus useful to reiterate the message of the preamble, that the herbal practitioner sees the herbal remedy as essentially supportive of body function, amphoteric rather than unilaterally active, promoting a vital body response to invasion or obstruction rather than aiming simply to remove the superficial characteristics of the latter. We thus find the herbal practitioner using Crataegus equally in cases of high and low blood presssure for its tendency to normalize this parameter. The evidence suggests that by supporting the function of the heart whilst also having vasodilatory action, may be something in this. We also find the practitioner using Vitex as a general normalizing remedy in a variety of gynaecological conditions, and we have the supporting contention that the remedy acts pivotally on the hypothalamicpituitary axis. Body function can be supported in more direct ways too. The use of the bitter remedies provokes a reflex response on the part of the body that is comprehensively useful in improving a range of functions associated with the body's relationship with food. It is contradicted only when that relationship is already marked by overactivity, for example in hyperacidity or vomiting. Otherwise, the bitter effect is clinically useful for many upper digestive problems, including such diverse conditions as anorexia, diabetes and hypoglycaemic cyndrom, hypochlorydia and tendency to enteric infections, chronic liver disease and liver-centred toxic problems. A third way to support vital function is by using trophic remedies; these are remedies which have an almost nutritious action on a specific organ or tissue. Simarianum, we say, demonstrated suchan action on the liver parenchymal cells, and in a sense we can see the same relationship to the adrenal cortex of Glycyrrhiza glabra, with its ACTH action and also yet its corticosteroid-enhancing effect in the periphery. Similarly the total action of Allium sativum on the blood stream can be considered trophic, improving a broad range of functional parameters and we have already witnessed the trophic effect of Crataegus on the heart. The action of herbal remedies in support of vital body function therefore comes in three categories, 1) the amphoteric regulation of excessive functional oscillation, 2) the direct provocation of a healthy reflex response and 3) the straightforward trophic effect. Central to any of these actions is the intrinsic complexity of each remedy's constitution. One very often finds constitutents present with apparantly contradictory isolated pharmacological actions, as for example in the water-retentive glycyrrhizin and other diuretic constituents in Glycyrrhiza; the impression gained is of a potentiating of individual contributions to the total action so that the whole plant is made up of more than the sum of its parts. Thus even in those remedies with an almost allopathic effect such as Allium with its antimicrobial action and Glycyrrhiza with its anti-inflammatory effect, there is sufficient complexity in both the active constituents of the plants and of other reported pharmacological effects to make it clear that we are not comparing them directly with allopathic counterparts. Evidence of supportive actions as outlined above in particular give each such remedy a much more founded and substantial effect overall, perhaps at the expense of the dramatic effect familiar in allopathic circles. This is only a fraction of the case that could be prepared for herbal medicine. Many more remedies would have to be discussed to provide the complete story. It is hoped, however, that sufficient has been said to make the point that herbal medicine is worthy of consideration as a valid health care alternative in the modern world. One is mindful of the comments of the World Health Organization on the role of traditional medicine where the facilities of modern medicine are lacking. The author would hope to make a plea that herbal remedies be considered in an even more positive light. Those with scientific training will perhaps contend that the use of scientific data to support a case for using techniques that cannot be completely validated or even explained by the rigours of the experimental method is a case of having the best of both worlds. To this the authormust answer that if it came to a conflict then the herbalist would turn his back on the experimental method rather than to the evidence of his won eyes and ears and that of his patients; however, there is no need for a conflict to occur, the scientific method does contribute to man's understanding of the world when used with enlightenment and true humility. It is to everyone's best interests to work together towards improving the quality of life and health.
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