RESUMO
BACKGROUND: Most patients with contact allergy to Asteraceae plants are patch test positive to sesquiterpene lactone mix (SLM). There are several reports among these patients of a flare-up of hand eczema after ingestion of food and beverages originating from Asteraceae plants. AIM: To investigate whether German chamomile tea can elicit systemic allergic dermatitis. PATIENTS AND METHODS: Individuals with or without contact allergy to SLM were patch tested with an extract of German chamomile tea. Six weeks later, they were provoked with capsules containing either freeze-dried German chamomile tea or placebo capsules containing lactose, in a double-blind, randomized study. A numerical rating scale (NRS) was used to ascertain the volunteers' opinion of their hand eczema status. The study individuals were examined to detect a possible flare-up of healed patch test reactions to chamomile. RESULTS: None of the subjects had a flare-up of healed patch test reactions. According to the NRS, SLM-positive individuals experienced a significant worsening of hand eczema, independently of whether they received chamomile or lactose capsules. CONCLUSION: No evidence suggestive of systemic allergic dermatitis was found.
Assuntos
Dermatite Alérgica de Contato/etiologia , Ingestão de Alimentos , Dermatoses da Mão/etiologia , Matricaria/efeitos adversos , Preparações de Plantas/efeitos adversos , Adulto , Idoso , Estudos de Casos e Controles , Dermatite Alérgica de Contato/fisiopatologia , Método Duplo-Cego , Feminino , Dermatoses da Mão/fisiopatologia , Humanos , Lactonas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Preparações de Plantas/administração & dosagem , Distribuição Aleatória , Sesquiterpenos/efeitos adversosRESUMO
BACKGROUND: Although German chamomile (Chamomilla recutita) is considered a weak sensitizer, recent studies have shown several possible non-sesquiterpene lactone allergens in tea (infusions) from the plant. OBJECTIVE: The aim of this study was to report the results of patch testing with herniarin (7-methoxycoumarin), which is one of the possible coumarin allergens in chamomile. PATIENTS/MATERIALS/METHODS: Between 1991 and 2009, selected patients with known or suspected Compositae contact allergy were patch tested with herniarin 1% petrolatum. RESULTS: Among 36 patients tested, there was one positive and three doubtful positive reactions to herniarin. All 4 patients had a relevant contact allergy to German chamomile, whereas the majority of the remaining 32 patients had chamomile allergy of unknown relevance. CONCLUSIONS: The clinical results suggest that herniarin indeed is one of the non-sesquiterpene lactone sensitizers in German chamomile and that sensitization may occur through, for example, external use of chamomile tea or use of chamomile-containing topical herbal remedies.
Assuntos
Bebidas/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Eczema/etiologia , Matricaria/efeitos adversos , Umbeliferonas/efeitos adversos , Corticosteroides/uso terapêutico , Adulto , Antibacterianos/uso terapêutico , Ciclosporina/uso terapêutico , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/tratamento farmacológico , Eczema/diagnóstico , Eczema/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Testes do Emplastro , Umbeliferonas/imunologiaRESUMO
No cases have been reported of Matricaria chamomilla potentiating the effects of warfarin. Nevertheless there is a theoretical risk for potentiation, since the herb is thought to be a coumarin constituent. We describe the case of a 70-year-old woman who, while being treated with warfarin, was admitted to hospital with multiple internal hemorrhages after having used chamomile products (tea and body lotion) to soothe upper respiratory tract symptoms. Patient education on the potential risk of taking chamomile products while being treated with warfarin is necessary to avoid such occurrences.