 |
|
Phytotherapeutic Approaches to Common Dermatologic Conditions
Donald J. Brown, ND;
Alan M. Dattner, MD
Arch Dermatol. 1998;134:1401-1404.
ABSTRACT
In this review, we discuss some common herbal preparations historically used for dermatologic conditions and recent studies that support their use. The traditional practice of topically treating dermatologic conditions with plant-derived medicines predates the cultures of ancient Egypt and remains vital today in the industrialized cultures of both the United States and Europe. Recent scientific studies lend support to some of the claims of herbal practitioners for the safety and efficacy of many herbs. The studies also elucidate, in some cases, the mechanisms by which these herbs act. With the growing interest in alternative and complementary therapies, practitioners need more information. Clinical studies and collected observations will help define specific indications for choice of herbal treatment based on both the skin disorder and the unique characteristics of the patient involved.
INTRODUCTION
A few topical herbal medicines such as Aloe vera are generally accepted as safe and efficacious medicines by dermatologists, primary care physicians, and research scientists. Regarding the safety and efficacy of many other herbal preparations, however, there is not such widespread agreement. Further studies and more organized systems of reporting and observation are needed to confirm or refute some interesting preliminary conclusions and to help define the place of herbal preparations in dermatologic therapeutics. The German system of regulating herbal medicines may provide the framework to further examine a prioritized list of these promising plant-derived medicines. Certain gaps exist within the German system, but the established practice of phytotherapy in that country can provide a practical basis for determining efficacy and safety.
This review of herbal approaches to common dermatologic conditions is intended to offer the dermatologist an introduction to commonly used herbal medicines in Germany and other European countries. The German system differs somewhat from ours, but the established practice of phytotherapy in that country can provide a practical basis for determining efficacy and safety.
ACNE
While there have been some reports of success using tannin-containing herbs such as witch hazel and oak bark as topical astringents for acne, no controlled studies showing efficacy are available in the literature. Historically, alterative ("blood cleansing") herbs such as burdock root (Arctium lappa) have been recommended by traditional herbalists as an internal approach to acne, eczema, and psoriasis.1(pp107-108) The underlying belief is that the skin is an organ with capabilities of elimination, which becomes diseased when the input of toxins is more than the liver, kidneys, and immune system can handle.
DERMATITIS
Calendula
Calendula officinalis, also known as pot marigold or common marigold, is an aromatic plant with yellow or orange flowers that are broken up to make herbal preparations. Calendula flower preparations have long been considered valuable topical remedies for burns, bruises, cuts, and rashes. In European folk medicine, they were also recommended for use internally as antispasmodics, diaphoretics, antihelminthics, and for treatment of eczema.2(pp118-120) They are currently recommended by the German health authorities for topical treatment of minor wounds and leg ulcers.3 Internal uses are limited to inflammatory lesions of the oral and pharyngeal mucosa.
Chemistry. Pentacyclic triterpene trihydroxyalcohols, flavonoids, and saponins have been isolated and may contribute to Calendula's anti-inflammatory and wound-healing actions topically.1(p1134)
Mechanism of Action. Flower, flower/herb combinations, and extracts have been ascribed anti-inflammatory, wound-healing, and immunomodulatory actions.4 Calendula is believed to stimulate granulation and increase glycoprotein and collagen metabolism at the wound site.
Clinical Use. Calendula is widely accepted as a topical treatment for diaper rash and other mild skin irritations or inflammation.
Recommended Use. Most topical use of Calendula flowers is in the form of an ointment or cream containing the equivalent of 2 to 5 g of the flower heads per 100 g of ointment, which is applied topically several times daily. A tea can be made for mouthwash or topical treatment by pouring 0.24 L of boiling water over 1 to 1.5 g of the flower heads and allowing it to steep for 10 minutes.5(p1578)
Safety. Topical as well as internal use of Calendula is generally safe. There have been rare reports of allergic contact dermatitis with topical use of Calendula.6
Chamomile
Chamomile (Matricaria recutita) is a member of the daisy family (Asteraceae) with distinctive yellow flowers with white rays. It is used for treatment of mild gastrointestinal tract conditions and as a mouthwash for irritation and inflammation of the oral mucosa. A number of topical products are also available for dermatitis and other mild irritations of the skin.
Chemistry. The flowers of chamomile contain 1% to 2% volatile oil.2(pp322-325) The key constituents in the volatile oil are  -bisabolol, -bisabolol oxides A and B, and matricin. Matricin is usually converted to chamazulene during the extraction process. German chamomile products are often produced to contain an established amount of chamazulene and -bisabolol. Chamomile flowers are also rich in flavonoids. The primary flavonoids are apigenin with smaller amounts of luteolin and quercetin.
Mechanism of Action. Chamomile extracts inhibit both cyclooxygenase and lipoxygenase in vitro.7 Both apigenin and quercetin inhibit histamine release from antigen-stimulated human basophilic polymorphonuclear leukocytes.8 According to a Tonelli croton oil ear assay, total chamomile extract and particularly its flavonoid fractions were very active following topical application.9 Apigenin was found to be the most active flavonoid . A test with 9 healthy female volunteers demonstrated that skin penetration of flavonoids was excellent following topical administration.10
Clinical Use. Most of the studies have been completed in Germany using a chamomile cream or ointment (Kamillosan, Astra Medica, Frankfurt, Germany). In one trial with humans, chamomile was found to have an effect that was 60% as active as 0.25% hydrocortisone when applied topically.11 In another trial, the chamomile ointment was effective in reducing dermatitis following a single application of sodium lauryl sulfate.12 A multicenter study of patients with atopic dermatitis13 showed that chamomile cream was "about as effective" as hydrocortisone and more effective than the other 2 topical preparations tested. Chamomile is also used for the treatment of minor wounds such as stasis ulcers in the elderly.14
Safety. Topical use of chamomile is extremely safe. There have been rare reports of contact dermatitis following topical application of the herb.15
Witch Hazel
Witch hazel (Hamamelis virginiana) has a long history of use in both traditional herbal medicine and allopathic medical practice for treatment of hemorrhoids, burns, cancer, tuberculosis, colds, and fever.16 Topical preparations have also been used for symptomatic relief of itching and minor skin inflammation. Distilled witch hazel extracts available over-the-counter in the United States are virtually devoid of the tannins that are thought to be of use in the treatment of dermatitis.5(pp151-152)
Chemistry. Witch hazel leaves contain approximately 7% to 10% tannins, primarily gallotannins with some condensed catechins and proanthocyanidins.2(pp245-247)
Mechanism of Action. As is the case with other tannin-containing herbs (eg, oak bark and horse chestnut), witch hazel is a powerful astringent. Tannins are thought to be useful in dermatitis because they coagulate surface proteins of cells, leading to a reduction in permeability and secretions.17 These precipitated proteins tend to form a protective layer on the skin.
The anti-inflammatory activity of 2 concentrations of witch hazel distillate (0.64 mg Hamamelis ketone/100 g and 2.56 mg Hamamelis ketone/100 g) were compared with 1% hydrocortisone, chamomile cream (Kamillosan), and 4 base preparations.18 The witch hazel extract (Hametum) in a base of phosphotidyl choline was shown to reduce erythema induced by UV radiation and cellophane tape stripping in 24 healthy subjects almost as well as 1% hydrocortisone.
Clinical Use. The German Commission E monograph lists mild damage and inflammation of the skin as indications for the topical use of witch hazel.19 A witch hazel–phosphotidyl choline product (Hametum) was slightly more effective than bufexamac ointment in a double-blind trial of 22 patients with atopic dermatitis of the lower arms.6 In another clinical trial, 2 groups of subjects with atopic dermatitis (n=36 subjects), and contact dermatitis (n=80 subjects) were treated with witch hazel extract or a control preparation (substance not given).20 In the atopic but not the contact dermatitis group, the witch hazel extract was somewhat superior to the control substance in reducing inflammation and itching. Anecdotal success in using the witch hazel–phosphotidyl choline cream has been reported in the management of atopic dermatitis in young children.21
Recommended Use. For topical use, a leaf extract supplying 5% to 10% of the drug can be applied to the affected area several times daily.
Other Herbal Approaches to Dermatitis
Licorice root (Glycyrrhiza glabra and Glycyrrhiza uralensis ) is commonly used in traditional Chinese herbal medicine combinations for atopic dermatitis. A traditional formulation of 10 herbs (Zemaphyte) including licorice root has been widely studied in Great Britain for atopic dermatitis. The combination has proven successful in a long-term study of children22 and a short-term study of adults.23 Due to the bitter taste of the decoction made from the powdered herbs, compliance has been a problem. Concern has also been raised about mineral corticoid-like adverse effects and hepatotoxicity with long-term use.
Glycyrrhizin, a saponin of licorice root, and its derivative, glycyrrhetinic acid (GA), have been found to inhibit 11 -hydroxysteroid dehydrogenase, the enzyme that catalyzes conversion of cortisol to cortisone.24 One study found that 2% GA combined with hydrocortisone enhanced the local effects of the hydrocortisone.25 Because GA is already touted as a topical anti-inflammatory for dermatitis and psoriasis,26 this may point to a potential concomitant use of GA with hydrocortisone not only to enhance local effects but also to reduce systemic adverse effects. Further studies are needed to test this hypothesis.
Interestingly, a similar effect was noted when aloe (A vera) gel was tested as a vehicle for hydrocortisone.27 The combination was tested systemically and topically for acute inflammation in mice. In both tests, there was a greater anti-inflammatory effect noted with the combination than with hydrocortisone alone.
PSORIASIS
While some of the topical anti-inflammatory herbal agents used to treat dermatitis may prove useful for the management of psoriasis, there are fewer data on the use of herbal medicines for this condition. Perhaps the best plant-derived product for psoriasis is capsaicin, the pungent principle in cayenne pepper. Two clinical trials have demonstrated the efficacy of 0.025% capsaicin cream (Zostrix) in the treatment of psoriasis. The first study of 44 patients with moderate and severe psoriasis vulgaris found that application of capsaicin cream led to a significant reduction in scaling and erythema over a 6-week period.28 The second study of 197 patients with pruritic psoriasis used the same cream (applied 4 times daily) and found that scaling, thickness, erythema, and pruritis were all substantially reduced over a 6-week period.29 In both studies, the most frequently reported adverse effect was a transient burning sensation at the site of application.
Better known for its topical use in wound healing and for the treatment of minor burns, aloe (A vera) has shown potential as a topical treatment for psoriasis in a study completed in Punjab, Pakistan.30 Sixty subjects, aged 18 to 50 years, with slight to moderate chronic plaquelike psoriasis were recruited for this study. Subjects were randomized to receive either aloe extract (0.5%) in a hydrophilic cream or placebo topically applied 3 times daily for a maximum of 4 weeks. The aloe group had a significantly (P<.001) greater improvement (83.3%) than the placebo group (6.6%). The aloe group also showed a greater number of healed chronic plaques (82.8%) compared with the placebo group (7.9%).
Many practitioners of natural medicine believe that some people have problems with clearing toxins from the body. These practitioners advocate the use of herbs to support liver function. It is interesting to note that one study of young male patients with psoriasis indicates a strong correlation between a history of alcohol abuse and psoriasis.31 An extract of milk thistle standardized to the flavonolignan silymarin has been advocated as a possible adjunctive approach to supporting the clearance of toxins by the liver.32 Silymarin is approved for alcohol-related liver disease in Germany.33 While anecdotal reports have suggested some benefit from use of milk-thistle extracts to treat psoriasis, clinical studies to support this theory are needed.
HERPES SIMPLEX LABIALIS
Lemon Balm
Lemon balm (Melissa officinalis) is a perennial herb, originally native to the eastern Mediterranean region, that has a distinctive odor of lemon.
Chemistry. The leaves contain approximately 0.1% to 0.2% volatile oil. Among the chief constituents in the oil are citronella, citral-A, citral-B, and other monoterpenes and sesquiterpenes.5(p1656)
Mechanism of Action. Water extracts of the leaves have noted antiviral properties in vitro and have been shown to have a viricidal effect against herpes simplex virus type 1.34
Clinical Use. Two studies using a topical preparation of dried lemon balm extract 1% cream (Lomaherpan) were reported in 1994.35 The first trial included 115 adult patients who were instructed to apply the lemon balm cream 5 times daily to the herpes lesion. Healing was complete in 96% of the patients at day 8; it was complete in 60% and 87% of the patients on days 4 and 6, respectively. Tolerance was excellent, with only 3 patients complaining of burning and paresthesia at the site of application.
The second trial reported was a randomized, placebo-controlled study of 67 subjects within 72 hours of onset of symptoms. The decline in the area of the lesion was greater and healing time was significantly faster (P<.01) in the lemon balm group than in the placebo group.
Plantain
Plantain (P Lantago major) is a common plant found on lawns, paths, and roadsides. The bruised leaves of the plant have a long history of topical use for insect bites and stings, as well as application to more serious conditions such as rattlesnake bites and tumors. One of us (A.M.D.) has observed the effectiveness of bruised leaves in reducing the itch and swelling from insect bites. A proprietary mixture (RE LEAF, ImmunoClarity Naturals) containing dried plantain leaf has also been useful in cases of insect bites and minor inflammations for which a drawing action is desired.
Clinical studies on the plant are limited to a report of its usefulness in poison ivy contact dermatitis36 and a report of its wound-healing properties.37 Physicians are more familiar with another product of the Plantago genus, the seed husk or psyllium seed, that is found in bulk laxatives (eg, Metamucil). The leaf contains mucilage that is made up of polysaccharides including mannose, galactose, dextrose, rhamnose, and levorotary arabinose.38 These could provide an osmotic gradient to draw allergens from bites or stings and might competitively inhibit irritating lectins. Flavonoids have also been found in the leaf. Five phenylethanoids in Plantago lanceolata were identified, and 1 of these compounds was shown to inhibit arachidonic acid–induced mouse ear edema.39 This observation may further explain the anti-inflammatory effects observed with plantain leaf applications. These effects are in sharp contrast to the well-known allergenic effects of plantain pollen and, to a lesser extent, plantain seed products.
COMMENT
Unless specifically referenced, some of the herbs mentioned herein need further study, both to document in an acceptable scientific manner their observed effects and to better define the indications for their most effective use. Redefinition of indications is especially important to integrate new laboratory and clinical data with information from alternative health approaches.
Many herbs are already being used by patients who seek care by dermatologists. Understanding their use and action helps the dermatologist integrate all elements of the patient's skin care regimen. The compilation of reports and observations of the effects of these herbs in patients with a variety of skin conditions will, along with further rigorous scientific studies, provide the basis for a more comprehensive knowledge of the usefulness of these herbs in clinical dermatologic practice.
AUTHOR INFORMATION
Accepted for publication July 2, 1998.
Reprints: Alan M. Dattner, MD, 17 Rodman Oval, New Rochelle, NY 10805.
From the President's Advisory Committee, Bastyr University of Natural Health Sciences, Seattle, Wash (Dr Brown); and ImmunoClarity Research Associates, New Rochelle, NY (Dr Dattner).
REFERENCES
1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics. New York, NY: John Wiley & Sons Inc; 1996.
2. Wichtl M. Herbal Drugs and Phytopharmaceuticals. Boca Raton, Fla: CRC Press Inc; 1994.
3. Committee of the Germany Federal Institute for Drugs and Medical Devices. Monograph Calendula flos. In: Blumenthal M, senior ed; Klein S, primary trans. The Complete Germany Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin, Tex: American Botanical Council; 1998:100.
4. ESCOP (European Scientific Cooperative on Phytotherapy) Secretariat. Proposals for European Monographs on Calendulae flos/Flos cum erba. Vol. 3. Bevrijdinglaan, Netherlands: ESCOP Secretariat; 1992.
5. Tyler VE. Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: Pharmaceutical Products Press; 1994.
6. Hörmann HP, Korting HC. Evidence for the efficacy and safety of topical herbal drugs in dermatology, I: anti-inflammatory agents. Phytomedicine. 1994;1:161-171.
7. Ammon HPT, Kaul R. Pharmakologie der Kamille und ihrer Inhalftsstoffe. Dtsch Apoth Ztg. 1992;132(suppl 27):3-26.
8. Middleton E, Drzewiecki G. Effects of flavonoids and transitional metal cations on antigen-induced histamine release from human basophils. Biochem Pharmacol. 1982;31:1449-1453.
FULL TEXT
| PUBMED
9. Della Loggia R. Lokale antiphlogistische Wirung der Kamillen-flavone. Dtsch Apoth Ztg. 1985;125(suppl 1):9-11.
10. Heilmann J, Merfort I, Hagerdorn U, Lippold BC. In vivo skin penetration studies of chamomile flavonoids. Planta Med. 1993;59(suppl):A638.
11. Albring M, Albrecht H, Alcorn G, Lucker PV. The measuring of the antiinflammatory effect of a compound on the skin of volunteers. Methods Find Exp Clin Pharmacol. 1983;5:75-77.
PUBMED
12. Nissen HP, Blitz H, Kreyel HW. Prolifometrie, eine Methode zur beurteilung der therapeutischen wirksamkeit kon Kamillosan®-Slabe. Z Hautkr. 1988;63:184-190.
PUBMED
13. Aergeerts P, Albring M, Klaschka F, et al. Vergleichende pruüfung von Kamillosan Creme gegenüber Steroidalen (0.25% hydrocortison, 0.75% flucortinbutylester and nichsteroidsalen (5% bufexamac) externa in der Erhaltungstherapie von Ekzemerkrankungen. Z Hautkr.. 1985;60:270-277.
PUBMED
14. Glowania HJ, Rauliin C, Swooda NI. The effect of chamomile on wound healing—a clinical double-blind study. Z Hautkr. 1987;62:1262-1271.
PUBMED
15. Mann C, Staba EJ. The chemistry, pharmacology, and commercial formulations of chamomile. In: Craker LE, Simon JE, eds.Herbs, Spices, and Medicinal Plants: Recent Advances in Botany, Horticulture, and Pharmacology. Vol. 1. Phoenix, Ariz: Oryx Press; 1986:235-280.
16. Witch hazel. Rev Natur Med Prod. St Louis, Mo: Facts and Comparisons; September 1990.
17. Laux P, Oschamann R. Witch hazel (Hamarnelis virginiana). Z. Phytolther. 1993;14:155-166.
18. Korting HC, Schäfer-Korting NM, Hart H, et al. Anti-inflammatory activity of hamamelis distillate applied topcially to the skin. Eur J Clin Pharmacol. 1993;44:315-318.
FULL TEXT
|
ISI
| PUBMED
19. Committee of the Germany Federal Institute for Drugs and Medical Devices. Monograph Hamamelidis folium. In: Blumenthal, M, senior ed; Klein S, primary trans. The Complete Germany Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin, Tex: American Botanical Council; 1998:571-573.
20. Pfister R. Problems in the treatment and after care of chronic dermatoses: a clinical study on Hametum ointment [in German]. Fortschr Med. 1981;99:1264.
PUBMED
21. Brown DJ. Herbal Prescriptions for Better Health. Rocklin, Calif: Prima Publishing; 1996:291.
22. Sheehan MP, Atherton DJ. One year follow-up of children tested with Chinese medicinal herbs for atopic eczema. Br J Dermatol. 1994;130:488-493.
FULL TEXT
|
ISI
| PUBMED
23. Lachman Y, Banerjee P, Poulter LW, et al. Association of immunological changes with clinical efficacy in atopic eczema patients treated with traditional Chinese herbal therapy (Zemaphyte). Int Arch Allergy Immunol. 1996;109:243-249.
ISI
| PUBMED
24. Whorwood CB, Sheppard MC, Stewart PM. Licorice inhibits 11-hydroxysteroid dehydrogenase messenger ribonucleic acid levels and potentiates glucocorticoid hormone action. Endocrinology. 1993;132:2287-2292.
ABSTRACT
25. Teeluksingh S, Mackie ADR, Burt D, et al. Potentiation of hydrocortisone activity in skin by glycyrrhetinic acid. Lancet. 1990;335:1060-1063.
FULL TEXT
|
ISI
| PUBMED
26. Evans FQ. The rational use of glycyrrhetinic acid in dermatology. Br J Clin Pract. 1958;12:269-279.
PUBMED
27. Davis RH, Parker WL, Murdoch DP. Aloe vera as a biologically active vehicle for hydrocortisone acetate. J Am Podiatr Med Assoc. 1991;81:1-9.
ABSTRACT
28. Bernstein JE, Parish LC, Rapaport M, et al. Effects of topically applied capsaicin on moderate and severe psoriasis vulgaris. J Am Acad Dermatol. 1986;15:504-507.
ISI
| PUBMED
29. Ellis CN, Berberian B, Sulica VI, et al. A double-blind evaluation of topcial capsaicin in pruritic psoriasis. J Am Acad Dermatol. 1993;29:438-442.
ISI
| PUBMED
30. Syed TA, Ahmad SA, Holt AH, et al. Management of psoriasis with Aloe vera extract in a hydrophilic cream: a placebo-controlled, double-blind study. Trop Med Int Health. 1996;1:505-509.
FULL TEXT
|
ISI
| PUBMED
31. Poikolainen K, Reunala T, Karvonen J, Lauharanta J, Karkkainen P. Alcohol intake: a risk factor for psoriasis in young and middle aged men? BMJ. 1990;300:780-783.
ISI
| PUBMED
32. Weber G, Galle K. The liver, a therapeutic target in dermatoses. Med Welt. 1983;34:108-111.
PUBMED
33. Leng-Peschlow E. Alcohol-related liver diseases—use of Legalon for therapy. Pharmedicum. 1994;2:22-27.
34. Dimitrova Z, Dimov B, Manolova N, et al. Antiherpes effect of Melissa officinalis L. extracts. Acta Mirobiol Bulg. 1993;29:65-72.
35. Wöbling RH, Leonhardt K. Local therapy of herpes simplex with dried extract of Melissa officinalis. Phytomedicine. 1994;1:25-31.
PUBMED
36. Duckett S. Plantain leaf for poison ivy. N Engl J Med. 1980;303:583.
PUBMED
37. Shipochliev T, Dimitrov A, Aleksandrova E. Anti-inflammatory action of a group of plant extracts [in Bulgarian]. Veterinarno-Meditsinski Nauki. 1981;18:87-94.
38. Murai M, Tamayama Y, Nishibe S. Phenylethanoids in the herb of Plantago lanceolata and inhibitory effect on arachidonic acid–induced mouse ear edema [letter]. Planta Med. 1995;61:479-480.
PUBMED
39. Brautigam M, Franz G. Schleimpolysaccharide aus Fpitzwegerichblattern. Dtch Apoth Zeit. 1985;125:58-62.
|
