There is very little information related to tea allergy secondary to ingestion. There are papers describing inhalational asthma due to dust from tea leaves (1,2). Tea is derived from the plant Camellia sinensis with the leaves utilized to prepare the tea beverage by warm to boiling water extraction. The mixture is complex with catechins being associated with immunologic responses. Unfermented tea (green) has a greater concentration of catechins and fermented, black tea the least. However, individuals with green tea allergy are reported to have positive skin test reaction to black tea (4). The predictive value of tests for specific-IgE are not confirmed. Testing was performed using 1 mg/ml to 1 ng/ml of tea extract powder (prepared by boiling tea leaves and then evaporating the liquid). The authors report a black tea ‘extract’ prepared by placing 1 gm of tea (presumed to be dried leaves) in 20 ml of normal saline for 30 minutes and then filtering with 0.45 um filter. It is not stated if the saline and tea leaves were room temperature or heated, although the same paper describes making various tea extract powders by boiling tea leaves in water, not saline, for 5 minutes and the ‘air drying’ to a powder. The powders were used to prepare the skin test concentrations at 1 mg/ml to 1 ng/ml. Both percutaneous and intradermal testing was performed. The threshold concentration that resulted in a positive skin test among the 3 patients reported ranged from 0.1 ug/ml to 10 ug/ml. However, the concentration of the oolong (black tea) used for testing was not clear to me.
I do not think a baseline tryptase would be necessary without a history of other reactions, although some might recommend. I do not think there is any relationship with the problems associated with tea ingestion and the COVID-19 vaccination.
There is a question in the archives of ATE discussing chamomile tea allergy, but this is not likely related to black tea.
In summary, the predictive value of allergy testing with tea is not known. The concentrations used for testing relied upon creating a powder, by evaporating the water used for extraction, and then resuspending the powder at concentrations ranging from 1 mg/ml to 1 ng/ml, with the threshold dose for a positive test reported to be 0.1-10 ug/ml. Another option would be to prepare tea with 1 gm of leaves, 20 ml of saline, filtering and testing with 1:1000 dilution to full strength by percutaneous method. Finally, Dr. Lieberman suggested a prick-to-prick test using wet tea leaves (see ATE question from archives below). I would not recommend intradermal testing, but others might consider. The risk/benefit of all of this is not clear to me and will require challenge regardless of findings. Thus, I would favor an open challenge without testing. I would start at 1:100,000-1,000,000 dilution of tea prepared as usual and increase 10-fold to full strength at 15-20 minute intervals. I would use a volume of 5 ml. If no reaction after full strength, I suggest ad lib drinking under observation.
A documented shared-decision making discussion would be necessary since there is risk in this process. There also may be variability in different tea preparations, so I am not confident you could be assured of safety of all future tea ingestion, black or otherwise.
1. Shirai, Toshihiro, et al. "Food allergy to green tea." Journal of allergy and clinical immunology 112.4 (2003): 805.
2. Shirai, Toshihiro, et al. "Epigallocatechin gallate-induced histamine release in patients with green tea-induced asthma." Annals of Allergy, Asthma & Immunology 79.1 (1997): 65-69.
3. Uragoda CG. Tea maker’s asthma. Br J Ind Med 1970;27:181-2.
4. Shirai, Toshihiro, Atsuhiko Sato, and Yukihiko Hara. "Epigallocatechin gallate: the major causative agent of green tea-induced asthma." Chest 106.6 (1994): 1801-1805.
I hope this information is of help to you and your practice.
All my best.
Dennis K. Ledford, MD, FAAAAI
2/2/2010: Anaphylactic reaction to tea?
A 40 year-old old patient with sensation of pharyngeal swelling and tachycardia within minutes of drinking tea. Patient known to have anaphylaxis with citrus so she thought there must have been a contamination with lemon juice. However, she recently drank black tea without lemon and no herbs that she knew of and developed hives, nausea, diarrhea, pharyngeal swelling, tachycardia and altered sensorium. She had great response to Benaadryl and to Epi times two. Patient has many pollen allergies as well. She also gets oral swelling and itch with mango ingestion. Is there much data on allergy to tea leaves? Any botanical cross reactivity?
Answer: Unfortunately I was unable to find, via a literature search, any documented anaphylactic reactions to black tea. The only anaphylactic reactions to tea that I could find were to camomile tea. A number of these have been reported not only by ingestion but also via enema. I have copied below a few abstracts for your information.
In the meantime, even though I could not find anaphylactic reactions to any other form of tea leaves other than camomile, it is certainly conceivable that your patient could have reacted to the tea. One thing you might consider doing is a prick-to-prick skin test to wet tea leaves, if you wish to document that the tea was the culprit. If you wanted to dilute the agent prior to doing a direct prick-to-prick test, you could soak the tea and then use the liquid tea itself. I would also advise, since the tea had been heated, to heat the tea and then let it cool prior to testing.
I do not know of any antigenic cross reactivity between tea and mango. Should you decide to test this patient, we would greatly appreciate a follow-up for our readers.
Allergol Int. 2009 Mar;58(1):135-6. Epub 2008 Dec 1.
Anaphylactic reaction to camomile tea.
Andres C, Chen WC, Ollert M, Mempel M, Darsow U, Ring J.
Department of Dermatology and Allergy, Technical University, Munich, Germany.
BACKGROUND: A type-IV-allergic reaction to German camomile (Matricaria chamomilla) in a form of allergic contact dermatitis is not unusual. However, only a few cases of anaphylactic reaction to camomile have been described in the literature. CASE SUMMARY: We present the case of a 38-year-old Caucasian man who developed an episode of severe anaphylaxis with generalized urticaria, angioedema and severe dyspnoea one hour after consuming camomile tea. Laboratory examination demonstrated a total serum IgE of 123 kU/l with specific IgE against camomile (4.94 kU/l, class 3). Skin prick test and labial provocation test with camomile showed a strong positive reaction. DISCUSSION: Our case confirms the presence of a type-I allergy to orally ingested camomile and indicates that the incidence and risk may be underestimated. Additional response to mugwort and pollen-derived food allergens should be evaluated in patients sensitised to camomile due to a higher incidence of allergic cross-reactivity.
Anaphylaxis to camomile: clinical features and allergen cross-reactivity.
Reider N, Sepp N, Fritsch P, Weinlich G, Jensen-Jarolim E.
Department of Dermatology, University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
BACKGROUND: Medicinal remedies of plant origin became very popular in recent years, and allergic reactions to these are on the rise, accordingly. Camomile has been reported as a potential trigger of severe anaphylaxis. The allergens responsible for camomile allergy have not been characterized as yet. OBJECTIVE: The present study aims at reviewing the clinical symptomatology of immediate-type reactions in a series of patients sensitized to camomile and at characterizing the responsible allergens. METHODS: Fourteen patients with a history of allergy either to camomile or to spices or weeds, and a positive skin prick test/RAST to camomile were investigated for related allergic reactions to food, pollen and others. IgE-binding patterns were determined by immunoblotting, inhibition tests and deglycosylation experiments. RESULTS: Ten of 14 patients had a clinical history of immediate-type reactions to camomile, in some cases life threatening. Eleven subjects were also sensitized to mugwort in prick or RAST, eight to birch tree pollen. Using a polyclonal rabbit anti-Bet v 1 antibody, a homologue of the major birch pollen allergen Bet v 1 was detected in two camomile blots. In four cases a group of higher molecular weight allergens (23-50 kDa) showed IgE-binding to camomile. All allergens proved heat stable. Binding was inhibited in variable degrees by extracts from celery roots, anize seeds and pollen from mugwort, birch and timothy grass. Deglycosylation experiments proved the presence of carbohydrate determinants in camomile which were not responsible for IgE-binding, though. Profilins (Bet v 2) were not detected in our camomile extracts. CONCLUSION: Incidence and risk of type I allergy to camomile may be underestimated. Concurrent sensitization to mugwort and birch pollen is not infrequent. Bet v 1 and noncarbohydrate higher molecular weight proteins were found to be eliciting allergens and are responsible for cross-reactivity with other foods and pollen.
J Allergy Clin Immunol. 1989 Sep;84(3):353-8.
Anaphylactic reaction after the ingestion of chamomile tea: a study of cross-reactivity with other composite pollens.
Subiza J, Subiza JL, Hinojosa M, Garcia R, Jerez M, Valdivieso R, Subiza E.
Centro de Alergia e Inmunologic Cl?nica, General Pardi?as, Madrid, Spain.
We report a case of an 8-year-old atopic boy in whom ingestion of a chamomile-tea infusion precipitated a severe anaphylactic reaction. The patient suffers from hay fever and bronchial asthma caused by a variety of pollens (grass, olive, and mugwort). This severe reaction was developed after his first ingestion of chamomile tea. Studies revealed the presence of immediate skin test reactivity and a positive passive transfer test to chamomile-tea extract. Moreover, both specific antichamomile-tea extract and anti-Matricaria chamomilla-pollen extract IgE antibodies were detected by an ELISA technique. Cross-reactivity among chamomile-tea extract and the pollens of Matricaria chamomilla, Ambrosia trifida (giant ragweed), and Artemisia vulgaris (mugwort), was demonstrated by an ELISA-inhibition study. These findings suggest a type I IgE-mediated immunologic mechanism as being responsible for the patient's anaphylactic symptoms and also suggest that the patient cross-reacted the pollens of Matricaria chamomilla contained in the chamomile tea because he was previously sensitized to Artemisia pollen.
Phil Lieberman, M.D.