Plants contain many constituents with local physical impact on body tissues. The topical use of herbal remedies is among the first emphases in the earliest and simplest traditions of healthcare. Wound healing was an obvious primal indication for which plant remedies appeared especially suitable.

From a modern perspective, direct effects on tissues are readily testable in research. Most antiseptic, anti-inflammatory and antitumour effects in the research literature relate to in vitro observations, of little direct application to anticipating the effects of oral consumption, but quite relevant to the prediction of topical activity.

Referral to Chapter 2 will provide much of the detail for this review. The following topical properties, however, can be highlighted.

Plant material often contains apparently soothing effects on physical contact and plant remedies must have been a very early instinctive application to wounds. Plants with high mucilage content form the basis of poultices and creams. Linum (linseed, flaxseed) is one of the most impressive poultices where the skin (or subdermal tissue in even unbroken skin) is painfully inflamed. Ulmus rubra (slippery elm bark) when powdered is one of the most obviously mucilaginous plant materials available for poultices. Stellaria (chickweed) in a cream base provides effective relief for many itchy conditions. Althaea (marshmallow root) and Trigonella foenum-graecum(fenugreek) have notably soothing reputations. The expressed juice of Aloe vera also has impressive topical demulcent properties when applied directly to broken or unbroken skin.^1–3

However, non-mucilaginous herbs like Alchemilla vulgaris (lady’s mantle) have also demonstrated topical healing effects, in this case on mouth ulcers.⁴ The anti-inflammatory remedy Boswellia has been shown topically to heal skin damaged by age and sunlight.⁵ The link between anti-inflammatory and healing properties is particularly well illustrated in an ex vivo study on an aqueous extract of Uncaria tomentosa (cat’s claw). The carboxy alkyl esters, in particular quinic acid esters, easily absorbed across the skin, have been shown to enhance DNA repair and skin resilience to UV damage through anti-inflammatory properties involving the inhibition of nuclear transcription factor kappaB (NF-kappaB).⁶

Perhaps the most thorough healing remedy is Symphytum (comfrey root) cream. When this is applied topically it combines an unparalleled local demulcent action, and tannins (see below) with an active promoter of repair, allantoin, which is known to be very rapidly absorbed into the subdermal tissue.⁷ Comfrey has demonstrated healing effects in controlled trials in ankle sprains,⁸ and even pain-relieving and anti-inflammatory effects (see below).

Tannins and related polyphenols are very common plant constituents with the simple property of curdling protein molecules into which they come in contact. The principle of tanning animal skins to make leather, most often using oak galls or oak bark, follows from this property. Simple washes with strong decoctions of high-tannin preparations (like broadleaved tree bark) are well-established country first-aid treatments for open wounds and third-degree burns and the technique was formally revived among ‘barefoot doctors’ in China after the Cultural Revolution in the 1960s. The aim here was to produce a sealing eschar over the exposed tissues formed from coagulated protein on the surface. In modern clinical application, suspensions of decoctions of high-tannin herbs in gum tragacanth or gum arabic can produce impressive healing effects in open wounds or skin lesions. Plants to be considered for this role include decoctions of Hamamelis (witchhazel bark), Potentilla tormentilla (tormentil root), Quercus (oak bark), Krameria (rhatany) and Geranium maculatum (American cranesbill root). The antioxidant effects of such preparations have also drawn attention.^9–11 Topically applied tea extracts have been shown to help to restore skin integrity in people with radiation-induced skin damage. On the basis of in vitro cell responses to various tea extracts, these effects are suggested to involve compounds other than the polyphenols.¹² The role of related polyphenols, the oligomeric proanthocyanidins (OPCs), in topical application has been suggested in a clinical study that pointed to a healing effect of combined oral and topical application of an OPC-rich pine bark extract in the treatment of ulcers of diabetic origin.¹³

The usefulness of application of green tea catechins for periodontal disease was investigated in a placebo-controlled trial.¹⁴ Strips containing the catechins as a slow release local delivery system were applied to oral pockets in patients once a week for 8 weeks. The pocket depth and amount of bacteria were markedly decreased in the tannin group, whereas there was no change for the placebo group.

A double blind study investigated the effect of chewing a green tea confectionery on gingival inflammation.¹⁵ A total of 47 volunteers (23 male, 24 female) were randomly assigned to chew either eight green tea or placebo candies per day for 21 days. While there was an improvement in the green tea group, the placebo group deteriorated slightly.

A number of plant constituents appear to possess topical anti-inflammatory effects, frequently in addition to their demulcent and astringent properties. They might be considered as alternatives to conventional steroidal and other anti-inflammatory prescriptions. For example, herbal Arnica extract compared well with topical non-steroidal anti-inflammatories in the relief of osteoarthritic pain.¹⁶ Calendula (marigold),¹⁷ at least when extracted in high-strength alcohol, and Matricaria recutita (German chamomile),¹⁸ both included in creams, have useful benefits in soothing inflamed skin lesions.¹⁹Berberis aquifolium²⁰ and Aloe vera²¹ have demonstrated efficacy in the treatment of psoriatic lesions. Echinacea applied topically appears to have local anti-inflammatory effects on minor wounds.²² Hypericum (St John’s wort) extracted in oil as a red pigment is a long-standing remedy for the relief of burns and skin pain, and a hyperforin-rich extract has shown benefit over placebo in relieving atopic dermatitis.²³ Other traditional remedies used topically for anti-inflammatory effects include Curcuma longa (turmeric), Juniperus (juniper oil) and Angelica archangelica (Angelica oil). Bruising is traditionally treated with external applications of Aesculus hippocastanum.²⁴ The antiseptic properties of tea tree oil (see below) are complemented with an observed topical antihistaminic effect.²⁵ Many of these applications are fully reviewed in the relevant monographs.

The comfrey ointment referred to above was evaluated for the treatment of knee arthritis.²⁶ In a large placebo-controlled clinical trial, 220 patients applied 2 g of ointment three times a day for 3 weeks to their painful knee joint. The ointment either contained comfrey or was a matching placebo. In terms of self-rated pain, there was a 55% drop in the comfrey group as opposed to a drop of only 11% in the placebo group. Similar results were also seen for other measures of osteoarthritis symptoms. Overall, pain was reduced, the mobility of the knee improved and quality of life increased.

Comfrey is also good for helping to relieve muscle pain. Two strengths of comfrey cream (10% and 1%) were tested in a double blind study involving 215 people with pain in either the upper or lower back.²⁷ The stronger cream caused significant improvements in pain on movement, pain at rest and pain on pressure.

A favourite herb for eczema and other forms of inflamed skin (dermatitis) and to promote healing is the Calendula marigold (Calendula officinalis). Radiation-induced dermatitis is a common side effect of radiation therapy. For approximately 80% of patients, irradiation induces dermatitis. Apart from the pain and inconvenience associated with the dermatitis, it can lead to interruption of the radiotherapy. There is no standard treatment for the prevention of radiation-induced dermatitis. A survey conducted in 2001 in France indicated that one-third of radiation oncologists prescribed a preventative topical agent for women undergoing irradiation for breast cancer; the most popular choice was the drug trolamine. Hence when French researchers initiated a trial of topical Calendula in patients receiving radiotherapy for breast cancer, they decided to compare its efficacy with that of trolamine.²⁸

Between July 1999 and June 2001, 254 patients who had been operated on for breast cancer and who were to receive postoperative radiation therapy were randomly allocated to application of either trolamine (128 patients) or Calendula ointment (126 patients) on the irradiated areas after each session. The occurrence of acute dermatitis of grade 2 or higher was significantly lower (41% versus 63%) with the use of Calendula than with trolamine. Patients receiving Calendula had less frequent interruption of radiotherapy and experienced significantly reduced radiation-induced pain. Calendula ointment was considered to be more difficult to apply, but self-assessed satisfaction was greater.

The topical effects of herbal remedies can include some antiseptic effects in vitro, although only a few whole preparations have significant clinical prospects. The antimicrobial effects of tea tree oil have been demonstrated in controlled clinical studies in acne vulgaris,²⁹ dandruff³⁰ and even methicillin-resistant Staphylococcus aureus (MRSA) infections.³¹ The oil also has established antifungal properties.^32,33 Another clinical study has demonstrated clinically relevant antifungal effects for a member of the Solanaceae (deadly nightshade) family.³⁴

Topical antiviral properties have been demonstrated for the concentrated extract of Melissa officinalis (lemon balm) in the relief of herpes infections.³⁵ One early study found an improved healing rate for 75% of patients, with the time between outbreaks prolonged in 50% of cases.³⁶ Compared with conventional treatments (at the time), the average healing time of lesions was halved to about 5 days and the time between outbreaks was approximately doubled.³⁶ In another multicentre study involving 115 patients, treatment of herpes lesions was commenced between 24 and 72 h from their outbreak.³⁷ It was found that lesions in 87% of patients were completely healed within 6 days of treatment. The time between outbreaks was increased for 69% of patients, and this was 2.3 months with lemon balm compared with 1.3 months for conventional drug treatments such as idoxuridine and tromantadine. Minor side effects were observed in only 3% of patients. The delay in new lesions occurring was without any prophylactic application, and it is possible that a preventative application of the cream to normally affected areas would further increase the time between outbreaks. Lemon balm cream can also be used to treat herpes simplex type 2 infection, and probably other similar viral skin infections, including shingles. The cream contained 1% of a concentrated 70:1 extract of lemon balm.

Rhubarb root (Rheum officinale) and sage (Salvia officinalis) also have activity against viruses, including herpes simplex type 1. In a double blind, controlled trial involving 49 patients, the results for creams containing either 2.3% sage, or 2.3% sage and 2.3% rhubarb, were compared against the conventional antiviral cream containing acyclovir. The average time for the herpes sores to fully heal was 7.6 days with the sage cream, 6.7 days with the rhubarb-sage cream and 6.5 days for acyclovir.³⁸ Hence, the herbal combination worked as well as the conventional drug.

Many herbs are used as a gargle, lozenge or throat spray to treat a sore throat. These include Calendula, sage, propolis, Echinacea root and golden seal. Acute viral pharyngitis is linked to the common cold and includes symptoms such as sore throat and fever. In a double blind, placebo-controlled clinical trial, the value of a sage throat spray was compared against a placebo spray in almost 300 patients with acute viral pharyngitis.³⁹ The throat spray was used for seven applications over 3 days, and each application consisted of three sprays. A 15% strength sage spray was found to be much better than placebo for relieving throat pain. Symptomatic relief occurred within 2 h of applying the spray.

For a further review of antimicrobial effects of herbal remedies see Chapter 2.

As well as the well-known effects on dental pain of topical Syzygium aromaticum (clove) oil,⁴⁰ and the impact on muscle pain⁴¹ and intractable itching⁴² of capsaicin preparations from Capsicum spp., there is now increasing evidence that comfrey (see above) also has pain-relieving properties in arthritis.⁴³

Fever is most often associated with viral and bacterial infectious illnesses of varying degrees of severity, such as ‘flu’, measles, rubella, rheumatic fever, pneumonia, malaria, scarlet fever, polio, tuberculosis and meningitis. It can also accompany a wider range of problems such as cardiovascular and autoimmune diseases, drug reactions and some cancers. Many cases, especially in children, remain mysterious.¹

It is therefore vital that the onset of any fever is diagnosed as accurately as possible, especially in the very young and elderly, pregnant women, among overseas travellers and those with immune disorders. Conventional drug therapy and even hospitalisation may be essential.

Perhaps because of the associations above, the fever process has come to be seen as a problem to be treated in its own right (‘We must bring the fever down’). The serious risks from hyperpyrexia (overheating) are well understood and the accompanying unpleasant symptoms are reason enough to regard fever with suspicion. However, if it is clear that fever is not part of a serious condition there are also good reasons for not suppressing the process unnecessarily. This view is gaining support in conventional medicine,^2,3 particularly in reaction to the fashion for using paracetamol, and previously aspirin, to treat common childhood fevers.⁴

A recent example of such concerns is the New Zealand study that investigated the association between infant and childhood paracetamol use and later atopy and allergic disease.⁵ Children given paracetamol before the age of 15 months were 3.6 times more likely to have atopy at age 6 years than infants who had not been given the drug. Paracetamol use between the ages of 5 and 6 years showed dose-dependent associations with wheeze and asthma.

Such modern reassessment of fever treatment echoes the older traditional view that fever was not the disease itself but the body’s extraordinary efforts to resist disease. It was therefore something to be supported, or at least managed, rather than unduly suppressed. In this view, a ‘good fever’, one which went through its natural course satisfactorily, would not only lead to better resolution of the immediate crisis but would actually rearm the body’s defences and increase its resistance to future onslaughts. Indeed, it was on this issue above all others that the revivalist practices of Samuel Thomson in the 19th century were based (see p. 11). It was common practice among ‘regular’ physicians to suppress fevers with mineral drugs based on mercury, arsenic and antimony. Thomson was moved by Indian practices, especially the sweat lodge, to vehemently challenge such principles and insist instead on the view that fever was a sign of healthy defences (the ‘natural heat’ of the body resisting ‘cold’ intrusion) and should be supported in its efforts rather than suppressed. To this end, he recommended the use of heating remedies, including cayenne, and other measures to support the body through the episode, managing excesses of the febrile condition along the way. Although Thomson’s message was simple (reflecting the predominance of fevers as the main clinical priority of the times), he identified a fundamental difference between traditional practices and the new direction of orthodox medicine – supporting body defences versus attacking disease processes.

Other traditional approaches to fever management were similar. Because fever was so common, the universal classification of remedies as heating or cooling was made very largely on the basis of their observed effects in this condition. Heating herbs would be used to support a flagging fever and, by promoting perspiration, were additionally seen as aiding elimination through the sweat glands (sweat glands do resemble primitive nephrons and can stand in for kidney function to some extent); cooling remedies would be used to temper excessive pyrexia. Herbs with subtle heating or cooling (such as the Galenic ‘hot in the first degree’) were seen as exerting a normalising effect, helping to steady body temperature. Other remedies were classified for their ability to reduce the impact of febrile convulsions, diarrhoea, vomiting and distress.

There is modern support for the traditional view.⁶ The body’s febrile response is accompanied by the arousal of powerful, unpleasant and debilitating defensive measures, the release of inflammatory chemicals, temperature-stimulated activity in the circulation and in various blood cells, including the scavenger white blood cells, and associated alterations in a wide range of other functions.^7,8 In many ways it is like inflammation, for which an analogous traditional view applies (see p. 152): it generally proceeds in defined stages, tends to be self-limiting and is directed to mobilising defensive resources to the rapid elimination of an intrusion into the tissues. Both inflammation and fever are accompanied by what may be regarded as guarding symptoms, in the case of fever often by nausea (leading to reduced eating and unnecessary digestive, eliminative and metabolic burdens), thirst (increasing fluid consumption and compensating for fever-induced dehydration), lassitude and exhaustion (ensuring adequate rest during the process) and photophobia (encouraging withdrawal to a darkened place so as to reduce visual and other stimulation).

In contrast to our forebears, modern practitioners can now accept the far superior diagnostic and treatment prospects that medicine can bring and be grateful that the killer fevers are largely in the past. Nevertheless, there is real value in revisiting some fundamental fever management approaches in the majority of feverish illnesses that do not present a serious threat. There is a real concern that suppressive measures like aspirin and paracetamol and pre-emptive (and often unsuitable) antibiotic treatments are aborting an important natural healing process. Earlier observers predicted that unresolved fevers would lead to recurrent low-grade problems thereafter. The current frequency of chronic catarrhal problems, sore throats, cervical lymphadenopathy (swollen glands), sinusitis, otitis media (glue ear) and atopic allergy, especially among children, reminds many modern practitioners of such a syndrome. Modern studies are beginning to validate these concerns (see above).

It is possible to retrieve some of the early measures as part of a new strategy of fever management, taking advantage of insights and technology unavailable to our forebears.

Fevers present serious challenges for any practitioner more used to dealing with modern chronic and low-grade conditions. Fevers can be dangerous. They can change rapidly and initial diagnoses can be wrong. It would be professionally negligent to take responsibility for managing a fever without the necessary personal medical qualifications and experience unless supported by an effective health team. The following suggestions can only be applied in such circumstances.

After best available medical diagnosis has determined that dangerous disease is unlikely, the phytotherapeutic approach to fever is to see the condition as something to be managed, even nurtured, to allow the body temperature to stay at acceptable febrile levels (usually the range 100–102°F or 37.8–38.9°C) until the fever breaks, then to switch to recuperative measures as required. During the fever the practitioner watches for dangerous symptoms (and ensures ongoing medical supervision as necessary), works with herbal and other measures to prevent body temperature rising too high and provides relief for ancillary symptoms like nausea, vomiting, diarrhoea, coughing, convulsions and general malaise and discomforts.

Many fever-causing bacteria and viruses either produce as metabolites, or present as surface antigens, trigger chemicals, referred to as exogenous pyrogens, that stimulate the temperature control mechanism in the hypothalamus – in effect, they ‘set the thermostat higher’. The result is a stimulus to the heat-generating and heat-conserving mechanisms of the body so that body temperature can rise to match the new setting in the hypothalamus. Such mechanisms include shutting down the blood flow to the surface (pallor), shivering and seeking warmth. In short, when the temperature is rising the patient feels cold.

This is the ‘chill’ phase of fever. When the body temperature rises to the level set by the hypothalamus, a new stability with balance of heat gain and loss returns. The symptoms of chill recede and a less uncomfortable phase commences.

With the rise in body temperature, blood flow through the tissues and the activity of the phagocytes increase. The body’s defences are alerted and mobilised. The intruder’s prospects are reduced, as eventually is its production of exogenous pyrogens. The upward stimulus on the hypothalamus is reduced and the thermostat setting falls. The outward sign of this change could be predicted from knowing that the body temperature will now be higher than that set in the thermostat so heat has to be lost. The circulation to the periphery opens up again, the sweat glands operate, clothing and coverings are thrown off. The temperature falls and for that reason the patient feels hot. In traditional terms, the fever has ‘broken’, ‘crisis’ has been reached and ‘lysis’ or resolution intervenes. With luck, the infection has been successfully rejected and recovery can commence.

There is a more complex story of course. For example, there are a range of cytokines, such as interleukin (IL)-1-(alpha and beta), IL-6 and tumour necrosis factor-alpha, produced by the body itself and known as endogenous pyrogens which, possibly interacting with prostaglandins, can induce relapsing and other complex fever patterns with no clear cause. More recently, it has been shown that inhibitors of cytochrome P450 exacerbate pyrexia and that inducing P450 arachidonic acid metabolism reduces fever.^9–11 There are also endogenous antipyretic mediators including neuroactive substances such as glucocorticoids, vasopressin, IL-10 and melanocortins.¹²

However, the summary account above provides an acceptable basis for a policy of fever management, in which basic principles of nursing can be augmented by herbal remedies.

The first requirement is for some means of monitoring the situation. A clinical thermometer is obviously central but its usefulness is greatly enhanced by knowing how to interpret its findings. Referring to the account of fever above will explain the following points:

With these clues and a thermometer, it is generally possible to assess progress through the fever. If, for example, the temperature was 104°F (40°C), its importance would depend on whether the patient was feeling hot or cold. In the former case, one would expect the temperature to fall; in the latter case, some quick treatment would be called for.

Apart from the usual techniques for bringing temperature down, such as cold wet face flannels or tepid baths, there is conventional aspirin.¹³ This, however, simply turns the thermostat controls down without attending to any other aspects of the fever; there is the risk of an unresolved problem with symptoms lasting for years.¹⁴

Its use in children has in any case been discontinued in recent years because of the incidence of serious side effects.^15,16 Paracetamol and ibuprofen¹⁷ are still used for similar purposes; there are reports of adverse effects in the case of paracetamol particularly,^18,19 but a recent systematic review indicates safety of these agents compared with nocebo effects is not a major concern.²⁰ The wider question is the wisdom of using such agents to bring down the fever, with consequent risks to antibody production and cell repair, when no other risk is present.²¹

Herbal remedies, by contrast, have a number of more complex effects on the body and on the febrile response. There are a number of peripheral antipyretic mechanisms associated with plant remedies,^22–24 including ginger,²⁵ fennel,²⁶ boldo²⁷ and Andrographis.²⁸ However, it is worth noting in the practical guides to fever management that follow, that the published evidence for efficacy in humans has been undermined by poor methodological quality of the studies.²⁹

Herbal treatments during fevers are best provided in the form of aqueous infusions or decoctions (see p. 126), either hot or warm depending on the wider context.

As a steadying influence, the peripheral vasodilators or diaphoretics are appropriate, including remedies such as Achillea (yarrow), Sambucus (elderflower), Matricaria (chamomile), Tilia (limeflowers), Nepeta cataria (catmint) and Eupatorium perfoliatum (boneset). Their effect in hot infusion, seen only in a febrile state, is subjectively to reduce chill and encourage cooling perspiration; they also have a variety of other useful benefits for the digestion, mucous membranes and neuromuscular system. They may be combined with peppermint tea for a more accelerated cooling effect.

For gentle but stronger reduction in febrile temperature, the cooling bitters, like Taraxacum (dandelion root), Gentiana (gentian root) and Cichorium (chicory root) and Erythraea (centaury), are favoured. They have the additional advantage of stimulating the otherwise dormant digestive system, thus helping to counter fermentation or infection arising from the gut. Throughout history some plants were particularly favoured for their fever-reducing properties; most were notable bitters as well as having a range of antipathogenic and anti-inflammatory properties. They are, however, inherently more powerful and should be applied with more caution and under closer supervision. They include Cinchona (Peruvian bark that later yielded quinine), various members of the Artemisia or wormwood family, Jateorhiza (calumba), Berberis vulgaris (barberry bark) and Hydrastis (golden seal).

Apart from body temperature, there are other symptoms of fever that need to be watched. Many, such as nausea, vomiting, diarrhoea, headaches, coughing, pains and spasms, can usually be controlled by the appropriate herbal remedy, covered elsewhere in this book. Accepting the potential value of the febrile reaction does not mean consigning the patient to unnecessary discomfort. There are of course danger signs as well (a pulse that does not rise with temperature as expected might herald meningitis; convulsions, although common enough in children, can disguise and exacerbate polio; a dry cough of measles can resemble that of pneumonia, which can also be heralded by rapid breathing rates; malaria remains impossible to diagnose without blood tests).³⁰ The untrained must not attempt to take full responsibility for any such treatment.