Allergic contact dermatitis from topical Chinese herbal medicine and generalized urticaria and angioedema from dietary supplementation: A case report

Introduction

In a study conducted in 1997, 42% of the population in the United States used complementary and alternative medicine, including herbal medicine and dietary supplements.[1] Because they are natural products—some with a long tradition of use—many people consider them safe and side-effect free. There are isolated reports of allergic reactions to herbal medicine and dietary supplements. A case of allergic contact dermatitis from a topical Chinese herbal medicine and generalized urticaria and angioedema from dietary supplements occurring in the same patient is described.

Case history

An 18-year-old Chinese patient applied a topical/external plaster, Riaxin, containing Chinese herbal medicine, for back pain. She used four plasters in sequence on two locations, each one being removed after 24 hours of application. The first one was applied on one location and the next three on the second location inferiorly on her lumbar spine. She developed pruritic erythematous papular eruption consistent with allergic contact dermatitis in the area of the plaster after the first application in the second location.

On the day of removal of the fourth plaster, she took two dietary supplements of mainly Western herbal content. They were Isotonix OPC-3, which she had taken daily about four times a week for the past year without previous reaction, and Tension Tamer Celestial Seasonings herb tea, which she was using for the first time. Within 15 minutes, she developed generalized urticaria and angioedema of her lips. There were no associated systemic features. She responded to prednisone 50 mg once daily for 9 days, mometasone furoate ointment 0.1%, and diphenhydramine hydrochloride 25 mg as needed, initiated by her family physician. She declined allergy-patch testing and oral challenge.

Ingredients of topical Chinese herbal medicine and dietary supplements

The ingredients of the external plaster, Riaxin (distributed by a natural product company in the US), include “all natural herbs,” Chinese herbs: Commiphora myrrha Engl., Panax notoginseng (Burk) F.H. Chen ex C. Chow, Impatiens balsamina L., Boswellia carterii Birdw, Clematis chinensis Osbeck, Liqusticum chuanxiong Hort., Acanthpanax gracilistylus W.W. Smith, Gentiana macrophylla Pall, and alcohol. The label on this preparation also includes warning of allergic contact skin reaction from its use.

The Isotonix OPC-3, manufactured in the US, claims to be “an isotonic capable dietary supplement” providing oligomeric proanthocyanidins. The ingredients include grape seed extract, red wine extract, pine bark extract (Pycnogenol), bilberry extract, citrus extract bioflavonoids, and potassium bicarbonate 93 mg in one capful. The label also states that “this product is not intended to diagnose, treat, cure, or prevent any disease.” This important statement is often not included in many other complementary and alternative medicine preparations.

The Tension Tamer Celestial Seasonings herb tea, also made in the US, contains chamomile flowers, Eleuthero ginseng root, peppermint leaves, cinnamon, ginger root, lemon grass, licorice root, catnip leaves, tilia flowers, natural lemon flavor, hops, and vitamins B6 and B12.

Discussion

The allergic reactions associated with Chinese herbal medicine and Chinese patent medicine of herbal origin have recently been reviewed.[2] They include Stevens-Johnson syndrome,[3] generalized maculopapular eruption,[4] acute urticaria,[5] exanthematous eruption,[6] and hypersensitivity myocarditis[7] from oral preparations. A case of acute bronchospasm from occupational exposure from inhaled Chinese herbal medicine in a practitioner of complementary and alternative medicine has recently been presented.[8]

The most common form of allergic reaction from Chinese herbal medicine is allergic contact dermatitis.[2,9] It is caused by topical Chinese patent medicine and prepackaged or freshly prepared topical Chinese herbal preparations from bone-setters who are Chinese kung fu masters treating rheumatic complaints or bone injuries.[8,10] Myrrh/mo yao is the putative allergen in allergic contact dermatitis from topical Chinese patent medicine.[11] Patch testing, particularly for myrrh, would be helpful to establish the diagnosis.

Among Western herbal medicine and dietary supplements, there are occasional reports of allergic reactions. They include photosensitivity from St. John’s wort,[12] hypersensitivity vasculitis from passion flower,[13] Melaleuca oil (tea-tree oil) dermatitis,[14] allergic skin reaction from echinacea[15] and hops,[16] bronchospasm from royal jelly,[17] and lupus-like syndrome from yohimbine.[18] Anaphylaxis[19] has been reported in chamomile, including one fatal case.[20]

The exact allergens causing allergic contact dermatitis and urticaria and angioedema in this patient are not clear as she declined patch testing and oral challenge. However, the topical external plaster, Riaxin, contains myrrh previously documented to be the putative allergen causing allergic contact dermatitis,[11] and is most likely responsible for the allergic contact dermatitis in this patient.

The patient developed acute generalized urticaria and angioedema of her lips within 15 minutes of taking two dietary supplements. The patient had taken the Isotonix OPC-3 previously for 1 year without any reaction, and she took Tension Tamer Celestial Seasonings herb tea for the first time. It is highly suggestive that the urticaria and angioedema is due to the second dietary supplement, which contains chamomile, previously documented to cause anaphylaxis including urticaria and angioedema. The patient required high-dose oral prednisone, topical steroid, and antihistamines for management.

The specific components in the Chinese herbal medicine or dietary supplements causing allergic reactions are usually difficult to establish. There are additional problems of herbal plant misidentification,[21] presence of prescription drugs,[22] and unknown contents.[23,24] Although myrrh and chamomile are present in the topical Chinese herbal medicine and dietary supplements, the confirmative tests could not be carried out. In addition, myrrh as a testing antigen is not available in a local patch-testing clinic. Hops and licorice root may also be responsible,[16] the latter present in an eight-herb preparation causing generalized maculopapular eruption.[4]

Besides allergic reactions, complementary and alternative medicine, including herbal medicine and dietary supplements, can result in other adverse reactions, and herb-herb and herb-drug interactions.[25,26] Physicians should be familiar with complementary and alternative medicine literature,[27-29] and inquiry into the use of complementary and alternative medicine should be part of history taking.[23] Patients should be given proper advice in the use of herbal medicine and dietary supplements,[30] and be encouraged to tell physicians of their use of complementary and alternative medicine (see the Figure).

Conclusion

This is the first case report of two types of cutaneous allergic reaction to complementary and alternative medicine including topical Chinese herbal medicine and oral dietary supplements occurring in the same patient. Physicians should include inquiry into the use of complementary and alternative medicine as part of history taking. Complementary and alternative medicine (herbal medicine and dietary supplements), if used by the patient, should be included in the differential diagnosis in the presence of an allergic reaction.

Acknowledgments

The author would like to thank Dr Glen Bowlsby for the patient referral, the Medical Library Service of the College of Physicians and Surgeons of BC for the literature search, and Ms S. Hasham for secretarial aid.

Competing interests

None declared.

Figure. Patient information handout on the safe use of natural health products.
(May be reproduced without permission and given to patients.)

H.C. George Wong, MD, FRCPC, FACP, FAAAAI

Dr Wong is a clinical associate professor in the Division of Allergy and Immunology in the Department of Medicine at the University of British Columbia, course director of the UBC CME Community-Based Allergy/Immunology Program, active staff at Vancouver General Hospital, and a member of the BCMA’s Alternative Therapies and Allied Health Committee.