Herbs
Herbs are increasing in Western diets as flavourings in food, as teas and also as medicines. They are often seen as beneficial and safe yet they must, like all plants, be treated as potential agents that can cause food allergy and intolerance. They can, for many, be a hidden problem.
In 1997, the market for herb-laden food and drinks was around $20 million, by 2001 the figure had jumped to $700 million. It is to easy to see these products as 'safe' when in fact they add a further element of complexity to the diet and for some can lead to unwanted symptoms that are not easily identified as being reactions to herbs.
Herbs, like all plants, have a complex chemical structure and it has been discovered that some of these have beneficial properties for treating ailments. This 'healing' effect of herbs can be a double edged sword. For example, if you take ginseng as a tonic to help give you more energy it could give rise to symptoms of over stimulation that at first look as if it is working for you when in fact you are experiencing a negative reaction.
One of the key aspects of herbal medicine is that it is gentle, if the action is too fast then I would suggest you suspect the herb as a possible problem.
One of the most common problem herbs is mint which has been around as a flavouring for sweets (candies) and toothpaste for many years. Reactions have included stomach upsets, and dermatitis, itching and swelling in the mouth. The following case illustrates how difficult identifying a herb as the problem can be.
A 26-year-old woman had a 12-month history of persistent dermatitis of the lips. Avoiding cosmetics, changing toothpaste, and various treatments failed to bring any relief. It was only after an acute flare up of her symptoms after dental treatment with a mint flavoured tooth cleaning powder that they were able to identify the problem as mint. Once she stopped using a mint-flavoured toothpaste the problem disappeared (5).
There are very few herbs that have not, at some time, been implicated in causing health problems. A few examples of the problems that have been recorded follow:
- Mullins and Heddle outlined five cases of adverse reactions to Echinacea: 2 individuals suffered anaphylaxis, 1 had an acute asthma attack 10 minutes after their first ever dose of Echinacea, 1 suffered recurrent episodes of mild asthma each time Echinacea was ingested, and 1 developed a rash within 2 days of ingestion which recurred when rechallenged (6).
- Bonamonte et al describe how one individual developed allergic contact dermatitis to the spearmint (2).
- Rhinoconjunctivitis and gastrointestinal problems were experienced as reactions to aniseed(3).
- Reactions to herbs can be life threatening. For example, cases of severe anaphylaxis have been reported as reactions to chamomile (7).
- Benito et al tested for reactions to various herbs. They found positive reactions to oregano, thyme, hyssop, basil, marjoram, mint, sage and lavender (1).
It is not only the ingestion of herbs that leads to problems. Use of creams and oils that contain herbs can lead to cases of dermatitis that seem to be unresponsive to treatment. The dermatitis usually clears when the offending herb is no longer used. Some of the herbs that have been implicated in this way are camomile, feverfew, arnica, tansy, and yarrow (4).
Anyone reacting to a number of herbs should consider checking for a salicylate sensitivity as virtually all herbs have a high salicylate content.
References
1. Benito M, Jorro G, Morales C, Pelaez A, Fernandez A. Labiatae allergy: systemic reactions due to ingestion of oregano and thyme. Ann Allergy Asthma Immunol 1996 May;76(5):416-8.
2. Bonamonte D, Mundo L, Daddabbo M, Foti C. Allergic contact dermatitis from Mentha spicata (spearmint). Contact Dermatitis 2001;45(5):298 .
3. Garcia-Gonzalez JJ, Bartolome-Zavala B, Fernandez-Melendez S, Barcelo-Munoz JM, Miranda Paez A, Carmona-Bueno MJ, Vega-Chicote JM, Negro Carrasco MA, Ameal Godoy A, Pamies Espinosa R. Occupational rhinoconjunctivitis and food allergy because of aniseed sensitization. Ann Allergy Asthma Immunol 2002;88(5):518-22.
4. Hausen BM. A 6-year experience with compositae mix. Am J Contact Dermat 1996 Jun;7(2):94-9.
5. Holmes G, Freeman S. Cheilitis caused by contact urticaria to mint flavoured toothpaste. Australas J Dermatol 2001 Feb;42(1):43-5.
6. Mullins RJ, Heddle R. Adverse reactions associated with echinacea: the Australian experience. Ann Allergy, Asthma, & Immuno 2002;88:42-51.
7. Reider N, Sepp N, Fritsch P, Weinlich G, Jensen-Jarolim E. Anaphylaxis to camomile: clinical features and allergen cross-reactivity. Clin Exp Allergy 2000 Oct;30(10):1436-43.
8. Rogers SN, Pahor AL. A form of stomatitis induced by excessive peppermint consumption. Dent Update 1995 Jan-Feb;22(1):36-7.
1. Benito M, Jorro G, Morales C, Pelaez A, Fernandez A. Labiatae allergy: systemic reactions due to ingestion of oregano and thyme. Ann Allergy Asthma Immunol 1996 May;76(5):416-8.
2. Bonamonte D, Mundo L, Daddabbo M, Foti C. Allergic contact dermatitis from Mentha spicata (spearmint). Contact Dermatitis 2001;45(5):298 .
3. Garcia-Gonzalez JJ, Bartolome-Zavala B, Fernandez-Melendez S, Barcelo-Munoz JM, Miranda Paez A, Carmona-Bueno MJ, Vega-Chicote JM, Negro Carrasco MA, Ameal Godoy A, Pamies Espinosa R. Occupational rhinoconjunctivitis and food allergy because of aniseed sensitization. Ann Allergy Asthma Immunol 2002;88(5):518-22.
4. Hausen BM. A 6-year experience with compositae mix. Am J Contact Dermat 1996 Jun;7(2):94-9.
5. Holmes G, Freeman S. Cheilitis caused by contact urticaria to mint flavoured toothpaste. Australas J Dermatol 2001 Feb;42(1):43-5.
6. Mullins RJ, Heddle R. Adverse reactions associated with echinacea: the Australian experience. Ann Allergy, Asthma, & Immuno 2002;88:42-51.
7. Reider N, Sepp N, Fritsch P, Weinlich G, Jensen-Jarolim E. Anaphylaxis to camomile: clinical features and allergen cross-reactivity. Clin Exp Allergy 2000 Oct;30(10):1436-43.
8. Rogers SN, Pahor AL. A form of stomatitis induced by excessive peppermint consumption. Dent Update 1995 Jan-Feb;22(1):36-7.