Contact allergies to dental materials in patients.

BACKGROUND: Concerns regarding contact allergies and intolerance reactions to dental materials are widespread among patients. Development of novel dental materials and less frequent amalgam use may alter sensitization profiles in patients with possible contact allergy. OBJECTIVES: To analyse current sensitization patterns to dental materials in patients with suspected contact allergy. METHODS: This retrospective, multicentre analysis from the Information Network of Departments of Dermatology (IVDK) selected participants from 169 834 people tested in 2005-2019 and registered with (i) an affected area of 'mouth' (and 'lips'/'perioral'), (ii) with the dental material in question belonging to one of three groups (dental filling materials, oral implants or dentures or equivalents) and (iii) with patch-testing done in parallel with the German baseline series, (dental) metal series and dental technician series. RESULTS: A total of 2730 of 169 834 tested patients met the inclusion criteria. The patients were predominantly women (81.2%) aged ≥ 40 years (92.8%). The sensitization rates with confirmed allergic contact stomatitis in women (n = 444) were highest for metals (nickel 28.6%, palladium 21.4%, amalgam 10.9%), (meth)acrylates [2-hydroxyethyl methacrylate (HEMA) 4.8%] and the substances propolis (6.8%) and 'balsam of Peru' (11.4%). The most relevant acrylates were HEMA, 2-hydroxypropyl methacrylate, methyl methacrylate, ethylene glycol dimethacrylate and pentaerythritol triacrylate. Few men were diagnosed with allergic contact stomatitis (n = 68); sensitization rates in men were highest for propolis (14.9%) and amalgam (13.6%). CONCLUSIONS: Allergic contact stomatitis to dental materials is rare. Patch testing should not only focus on metals such as nickel, palladium, amalgam and gold, but also (meth)acrylates and the natural substances propolis and 'balsam of Peru'.

Nutritional interventions for the prevention and treatment of cancer therapy-induced oral mucositis: an umbrella review of systematic reviews and meta-analysis.

CONTEXT: To date, the efficacy of nutritional interventions on oral mucositis (OM) in patients with cancer, and the quality of this evidence have not been explored. OBJECTIVE: The goal of this umbrella review was to provide a comprehensive evaluation of nutritional interventions for patients with cancer with OM, as well as to assess the quality of this evidence. DATA SOURCES: Meta-analyses were searched for using PubMed, Scopus, and ISI Web of Science databases until December 2021, with no time restrictions. DATA EXTRACTION: Meta-analyses of randomized control trials that evaluated the effects of nutritional interventions on the incidence of OM in patients with cancer had inclusion criteria for this umbrella review. Data extraction, quality assessment of meta-analyses, and primary studies were done independently by 2 authors. The Grading of Recommendations Assessment, Development, and Evaluation technique was used to grade the certainty of evidence. DATA ANALYSIS: A total of 26 meta-analyses were included in this umbrella review. The results showed that honey, glutamine, and propolis can reduce the incidence of severe OM, based on moderate evidence quality. In addition, zinc supplementation significantly reduced the incidence of OM, regardless of symptom severity; however, low certainty of the evidence was observed. The effects of vitamin E, curcumin, and probiotics on OM were not statistically significant. CONCLUSION: This umbrella review shows that honey, glutamine, and propolis can significantly reduce the incidence of severe OM. These findings need to be confirmed with well-designed, longitudinal randomized controlled trials. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42022301010.

The activity of propolis against pathogenic fungi isolated from human infections

Abstract Propolis is a resinous hive product collected by bees from the buds or other parts of plants. It is known for having various biological properties, including antifungal activity. Among the substances present in propolis, flavonoids and phenolic acids and their esters are responsible for its antifungal properties. This means that propolis is ideal for use as an antifungal agent in alternative medicine to treat a number of both topical and systemic infections caused by Candida species and other yeast-like fungi, dermatophyte and nondermatophyte moulds, without the serious side effects typical of synthetic treatment. It is also active against strains of fungi that are resistant to polyenes and azoles, the classes of drugs most commonly used to treat fungal infections. In this article, we review current knowledge about the activity of propolis from different parts of the world and its components in vitro and in vivo against pathogenic fungi isolated from human infections. The article also indicates the possible mechanism of antifungal activity of propolis and its components.

Red propolis reduces inflammation in cyclophosphamide-induced hemorrhagic cystitis in rats. / El propóleos rojo reduce la inflamación en la cistitis hemorrágica inducida por ciclofosfamida en ratas

Introduction. Cyclophosphamide (CP) is used to treat malignant neoplasias and control autoimmune diseases. Still, one of its metabolites, acrolein, is toxic to the urothelium and can lead to hemorrhagic cystitis and severe discomfort. Objective. To evaluate the ability of red propolis to prevent and treat CP-induced hemorrhagic cystitis in rats. Materials and methods. Red propolis was extracted in 1% gum arabic and administered subcutaneously (sc). In the first experiment, groups IA, IIA, and IIIA and groups IB, IIB, and IIIB received water, gum arabic (GA), or propolis, respectively, for 30 days. Then water (controls) or CP (treatment) was administered i.p. In the second experiment, groups IVA, VA, and VIA received water i.p. while groups IVB, VB, and VIB received CP i.p. This was followed by 5 injections at 2-hour intervals with either water, GA, or propolis. Bladder tissue was examined according to Gray's criteria. Results. The total inflammatory histology score was significantly smaller in group VIB (11.33 ± 2.07). Mild inflammation predominated in group VIB while most of the animals in group IVB had severe inflammation (p=0.0375). Ulcers were predominantly multiple in Groups IVA and VB but rare or absent in Group VIB (p=0.0118). Urothelial cells were mostly absent in groups IVB and VB and present/normal in group VIB (p=0.0052). Fibrin was abundant in groups IVB and VA but mostly absent in group VIB (p=0.0273). Conclusions. Red propolis can reduce inflammation in CP-induced hemorrhagic cystitis in rats.

Introducción. La ciclofosfamida se usa para tratar neoplasias malignas y controlar enfermedades autoinmunitarias, pero uno de sus metabolitos, la acroleína, es tóxico para el urotelio y puede provocar cistitis hemorrágica y malestar grave. Objetivo. Evaluar la capacidad del propóleos rojo para prevenir y tratar la cistitis hemorrágica inducida por ciclofosfamida en ratas. Materiales y métodos. Se extrajo propóleos rojo en goma arábiga al 1 % y se administró por vía subcutánea. En el primer experimento, los grupos IA, IIA, IIIA, IB, IIB y IIIB recibieron agua, goma arábiga y propóleos, respectivamente, durante 30 días. Luego se les administró agua (controles) o el tratamiento (ciclofosfamida) por inyección intraperitoneal. En el segundo experimento, los grupos IVA, VA, VIA recibieron agua por vía intraperitoneal, y los grupos IVB, VB, VIB recibieron el tratamiento por la misma vía, a lo que le siguieron cinco inyecciones con intervalos de dos horas entre ellas, con agua, goma arábiga o propóleos. El tejido de la vejiga se examinó de acuerdo con los criterios de Gray. Resultados. La puntuación total de la inflamación según la histología fue significativamente menor en el grupo VIB (11,33 ± 2,07). La inflamación leve predominó en este grupo, en tanto que la mayoría de los animales del IVB presentó inflamación grave (p=0,0375). Predominaron las úlceras múltiples en los grupos IVA y VB, pero fueron raras o estuvieron ausentes en el VIB (p=0,0118). En general, no se observaron células uroteliales en los grupos IVB y VB, pero sí en el VIB (p=0,0052). La fibrina fue abundante en los grupos IVB y VA, pero predominantemente ausente en el VIB (p=0,0273). Conclusiones. El propóleos rojo puede reducir la inflamación en la cistitis hemorrágica inducida por ciclofosfamida en ratas.

The use of standardized Brazilian green propolis extract (EPP-AF) as an adjunct treatment for hospitalized COVID-19 patients (BeeCovid2): a structured summary of a study protocol for a randomized controlled trial.

BACKGROUND: The 2019 coronavirus disease (COVID-19) pandemic continues to spread and affects large numbers of people with unprecedented impacts. Experimental evidence has already been obtained for use of the standardized extract of Brazilian green propolis (EPP-AF) against viral targets, and clinical rationality has been demonstrated for testing this extract as an adjunct to treatment in patients affected by COVID-19. The BeeCovid2 study aims to assess whether EPP-AF has an impact on the improvement of patients hospitalized with COVID-19 by reducing the length of hospital stay. METHODS: BeeCovid2 is a randomized, double-blinded, placebo-controlled clinical study being conducted in Brazil to provide further evidence on the effectiveness of standardized green propolis extract as an adjunctive treatment for adults hospitalized with COVID-19. Hospitalized patients over 18 years of age with a confirmed diagnosis of COVID-19 and up to 14 days of symptoms were included. Patients under mechanical ventilation at randomization, pregnant women, cancer patients, transplanted or using immunosuppression, HIV patients, patients who used propolis in the last 30 days, bacterial or fungal infection at randomization, impossibility of using medication orally or enterally, and advanced chronic diseases (e.g., advanced heart failure, severe liver disease, and end-stage chronic kidney disease). Enrolled patients are randomized at a 1:1 ratio to receive placebo or standardized propolis extract (900 mg/day) for 10 days. The study treatments are administered in a double-blinded manner, and patients are followed for 28 days. The primary outcome is the difference in length of hospital stay in days between groups. Secondary outcomes include the need for mechanical ventilation, the rate of secondary infection, rate of acute kidney injury, the need for renal replacement therapy, the requirement for vasoactive drugs, the use of an intra-aortic balloon pump (IABP), and the use of extracorporeal membrane oxygenation (ECMO). DISCUSSION: This trial is very useful and will provide more data on the effectiveness of using the standardized Brazilian green propolis extract as an adjunctive treatment in association with standard care in adults hospitalized with moderate to severe acute COVID-19. TRIAL REGISTRATION: ClinicalTrials.gov NCT04800224 . Registered on March 16, 2021.

Increased Expression of RUNX2 and ALP Resulting from a Combination of Propolis Extract and Bovine Bone Graft in Socket Preservation Material

Abstract The aim of this study was to determine the inductive effect of a combination of propolis and BBG extract on RUNX2 and ALP expression in the tooth extraction sockets of Cavia cobaya. Fifty- six Cavia cobaya were divided into four groups: polyethylene glycol (PEG), propolis extract + PEG, BBG + PEG, and propolis extract + BBG + PEG. The lower left incisor was extracted, and the socket subsequently filled with material according to the specific group of which the subject was a member. The subjects were sacrificed on the 14th and 30th days. Immunohistochemical staining was carried out under a light microscope at 400x magnification. Statistical analysis was then carried out by means of One-Way ANOVA and Tukey HSD tests. The mean number of RUNX2 and ALP expressions in each group was significantly different. The highest number of RUNX2 and ALP expressions occurred in the propolis + BBG + PEG group on the 30th day, while the lowest expressions were observed in the control group on the 14th day. A combination of propolis and BBG extract at a concentration of 2% of active substance effectively increases the expression of RUNX2 and ALP in preserving the tooth extraction sockets of Cavia cobaya.

Stingless bee propolis, metformin, and their combination alleviate diabetic cardiomyopathy

Abstract Background and aim: Stingless bee propolis, a resinous compound processed by mandibular secretion of stingless bees, is used for maintenance of hygiene and stability of beehives. Research on stingless bee propolis shows therapeutic properties attributed to polyphenols exhibiting antioxidative, antihyperglycemic and antiischemic effect. However, the cardioprotective effect of stingless bee propolis on diabetic cardiomyopathy is unknown. Methods: Adult male Sprague Dawley rats were randomised to five groups: normal group, diabetic group, diabetic given metformin (DM+M), diabetic given propolis (DM+P) and diabetic given combination therapy (DM+M+P) and treated for four weeks. Body weight, fasting blood glucose, food and water intake were taken weekly. At the end of experiment, biomarkers of oxidative damage were measured in serum and heart tissue. Antioxidants in heart tissue were quantified. Part of left ventricle of heart was processed for histological staining including Haematoxylin and Eosin (H&E) stain for myocyte size and Masson's Trichrome (MT) stain for heart fibrosis and perivascular fibrosis. Results: Propolis alleviated features of diabetic cardiomyopathy such as myocyte hypertrophy, heart fibrosis and perivascular fibrosis associated with improvement in antioxidative status. Conclusion: This study reports beneficial effect of propolis and combination with metformin in alleviating histopathological feature of diabetic cardiomyopathy by modulating antioxidants, making propolis an emerging complementary therapy.

Allergic contact cheilitis caused by propolis: case report

ABSTRACT Propolis is a lipophilic resin extracted from plants by bees. The purpose of this case report was to show the importance of this substance as cause of allergic contact cheilitis. A 21-year-old female patient complained of pruritic perioral eczema for 5 years. In the past months it also affected the neck. After diagnosing contact dermatitis, she was submitted to a patch test with a Latin American baseline series. The result was strongly positive for propolis (++) and weakly positive for perfume mix I (+). After the test, the patient revealed she had been using propolis drops, per oris, for 10 years. The worsening of the condition was due to increased dose, aiming "to improve immunity", during the coronavirus disease 2019 (COVID-19) pandemic. The contact allergy to propolis might be increasing due to the widespread use of natural products. Propolis is a sensitizer to be considered in patients with long-lasting cheilitis.

Propolis as an Adjuvant in the Healing of Human Diabetic Foot Wounds Receiving Care in the Diagnostic and Treatment Centre from the Regional Hospital of Talca.

OBJECTIVE: Diabetic foot wounds are a relevant diabetes complication and a major health problem. It has been described that propolis has health benefits due to its anti-inflammatory, antioxidant, and support in the healing process. The current study assessed the effect of propolis as an adjuvant in the healing of human diabetic foot ulcers. This was evaluated in a randomized placebo-controlled study of subjects receiving care in the Diagnostic and Treatment Centre from the Regional Hospital of Talca, Chile. RESEARCH DESIGN AND METHODS: Randomized subjects received ambulatory healing treatment for diabetes foot wounds with propolis spray (3%), which was applied to cover the entire wound surface each time it was dressed from week 0 until cicatrization or 8 weeks as a maximum. Two serum samples were taken (day 0 and end of the study) for cytokine and oxidative stress analyses. Also, macro- and microscopy were analyzed in the process of wound healing. RESULTS: The study comprised 31 subjects with type 2 diabetes in treatment for diabetic foot wounds in the Diagnostic and Treatment Centre from the Regional Hospital of Talca. Propolis promotes a reduction of the wound's area by an average of 4 cm2, related to an increase in the connective tissue deposit compared to the control. Also, propolis increased the glutathione (GSH) and GSH/glutathione disulfide (GSSG) ratio (p < 0.02), depleted tumor necrosis factor- (TNF-) α, and increased interleukin- (IL-) 10 levels. Topical propolis did not modify the biochemical parameters in the serum of the studied subjects. CONCLUSIONS: The topical use of propolis turned out to be an interesting therapeutic strategy as an adjuvant in the care of diabetes foot wounds due to its ability to improve and promote healing based on its anti-inflammatory and antioxidant profile. This trial is registered with NCT03649243.

Dual effect of Algerian propolis on lung cancer: antitumor and chemopreventive effects involving antioxidant activity

Abstract The purpose of our study was to divulge the antiproliferative effect of an ethanolic extract of Algerian propolis (EEP) in the human lung adenocarcinoma cell line (A549) and reveal the chemopreventive role against benzo(a)pyrene-induced lung carcinogenesis in albino Wistar rats. Cytotoxicity of EEP was evaluated using the MTT assay and cell adhesion in A549 cells. Moreover, rats were given 25 mg/kg of propolis for 5 days before induction of experimental lung cancer by a single intraperitoneal dose of 200 mg/kg benzo(a)pyrene. Body weight, lung weight, lipid peroxidation, marker enzymes, and enzymatic and non-enzymatic antioxidants were estimated. The EEP demonstrated an inhibitory effect on proliferation of A549 at 24 and 72 hours in a dose-dependent manner and blocked adhesion of the cells by fibrinogen. Moreover, EEP reduced the oxidative stress generated by benzo(a)pyrene. The pre-treatment showed that enzymatic and non-enzymatic antioxidants increased and lipid peroxidation decreased. A histological analysis further supported these findings and showed a decrease in the number of side effects. These results are particularly important for both clinical applications of propolis and the possibility for its use as a potential chemotherapeutic agent.

Biological Activities of Red Propolis: A Review.

BACKGROUND: The red propolis (RdProp) is a resin produced by Apis mellifera bees, which collect the reddish exudate on the surface of its botanic source, the species Dalbergia ecastophyllum, popularly known in Brazil as "rabo de bugio". Considered as the 13th type of Brazilian propolis, this resin has been gaining prominence due to its natural composition, rich in bioactive substances not found in other types of propolis. OBJECTIVE: This review aims to address the most important characteristics of RdProp, its botanical origin, the main constituents, its biological properties and the patents related to this natural product. METHOD: By means of the SciFinder, Google Patents, Patus® and Spacenet, scientific articles and patents involving the term "red propolis" were searched until August 2017. RESULTS: A number of biological properties, including antimicrobial, anti-inflammatory, antiparasitic, antitumor, antioxidant, metabolic and nutraceutical activities are attributed to RdProp, demonstrating the great potential of its use in the food, pharmaceutical and cosmetics industries. CONCLUSION: The available papers are associated to pharmacological potential of RdProp, but the molecular mechanisms or bioactive compounds responsible for each activity have not yet been fully elucidat ed. The RdProp patents currently found are directed to components for the pharmaceutical industry (EP2070543A1; WO2014186851A1; FR3006589A1; CN1775277A; CN105797149A; CN1879859A), cosmetic (JP6012138B2; JP2008247830A; JP6012138B2) and food (JP5478392B2; CN101380052A; WO2006038690A1).

Biological and therapeutic properties of bee pollen: a review.

Natural products, including bee products, are particularly appreciated by consumers and are used for therapeutic purposes as alternative drugs. However, it is not known whether treatments with bee products are safe and how to minimise the health risks of such products. Among others, bee pollen is a natural honeybee product promoted as a valuable source of nourishing substances and energy. The health-enhancing value of bee pollen is expected due to the wide range of secondary plant metabolites (tocopherol, niacin, thiamine, biotin and folic acid, polyphenols, carotenoid pigments, phytosterols), besides enzymes and co-enzymes, contained in bee pollen. The promising reports on the antioxidant, anti-inflammatory, anticariogenic antibacterial, antifungicidal, hepatoprotective, anti-atherosclerotic, immune enhancing potential require long-term and large cohort clinical studies. The main difficulty in the application of bee pollen in modern phytomedicine is related to the wide species-specific variation in its composition. Therefore, the variations may differently contribute to bee-pollen properties and biological activity and thus in therapeutic effects. In principle, we can unequivocally recommend bee pollen as a valuable dietary supplement. Although the bee-pollen components have potential bioactive and therapeutic properties, extensive research is required before bee pollen can be used in therapy. © 2016 Society of Chemical Industry.

Influência da própolis sobre os perfis leucocitário e proteico de camundongos e tempo de fechamento de feridas excisionais limpas e infectadas por Staphylococcus aureus / Influence of Propolis on leukocyte and protein profiles of mice and closing time of excisional wounds clean and infected by Staphylococcus aureus

RESUMO Este estudo teve como objetivo avaliar os efeitos da própolis sobre os perfis leucocitário e protéico de camundongos e sobre o tempo de fechamento de lesões de pele confeccionadas experimentalmente, limpas e infectadas com Staphylococcus aureus. No primeiro, foram utilizados 48 animais divididos em quatro grupos, sendo um tratado com solução hidroalcóolica pura e três tratados com própolis a 10%, nas dosagens de 20 mg, 40 mg e 80 mg por animal de 25 gramas de peso, em única aplicação intraperitoneal. Foram coletadas amostras de sangue no segundo, 10º, 18º e 26º dias após o tratamento para realização de leucograma, proteinograma e fracionamento eletroforético das proteínas. Na avaliação da atividade cicatrizante, também foram utilizados 48 camundongos divididos em seis grupos, nos quais realizou-se a confecção cirúrgica de feridas na dimensão de 1cm2, após anestesia dissociativa. Dois grupos serviram como controle para feridas limpas e infectadas. Dois grupos de feridas infectadas por S. aureuse dois grupos de feridas limpas foram tratados com própolis a 5% e 10%, sendo a escolha destas concentrações baseada em um estudo piloto realizado. Os resultados mostraram que o tratamento com própolis influencia o leucograma e o proteinograma, de forma dose-dependente, sendo que a maior dose utilizada desencadeou leucocitose com linfocitose e aumento de proteínas da fração gamaglobulínica, no 10º dia após o início do tratamento. Também mostraram que a concentração da solução influenciou o tempo de cicatrização das feridas infectadas, ocorrendo em menor tempo no grupo tratado com a solução a 5%.

ABSTRACT This study aimed to evaluate the propolis effects on both the leukocyte and protein profiles of mice and on the closing time of skin lesions made experimentally, clean and infected with Staphylococcus aureus. The first 48 animals were divided into four groups, one treated with pure alcohol solution and three treated with propolis 10% at dosages of 20 mg, 40 mg and 80 mg per 25 g of animal weight in an intraperitoneal single application . Blood samples in the second, and then 10º, 18º and 26º days after treatment were collected in order to perform WBC, proteins and electrophoretic fractionation of proteins. Regarding the healing activity, also 48 mice divided into six groups were used, in whom surgical wounds in the size of 1cm2 were purposely inflicted , after the dissociative anesthesia were applied . Two groups served as control ones, for clean and infected wounds. Two groups of S. aureus with infected wounds and two groups with clean sores were treated with 5% and 10 % propolis, being this concentration choice based on a pilot study previously performed. The results showed that treatment with propolis influences leukocyte and protein concentrations in a dose- dependent manner, with the highest dose triggering leukocytosis with lymphocytosis and increasing the protein fraction of gamaglobulínica, on the 10th day after the start of treatment. It also indicated that the concentration of the solution influence the time of healing of infected wounds, since the process on the group treated with 5% solution happened faster.

Propolis-induced descending necrotizing mediastinitis and aspiration pneumonia.

Propolis is a resinous substance collected by bees as a sealant for their hives. It is also used in traditional medicine as an antioxidant and antiinflammatory agent to treat ulcers, superficial burns, and microbial diseases. In this report, a 40-year-old woman who took liquid propolis for relief of her common cold experienced severe sore throat, dysphagia, and easy choking followed by fever and chills. Descending necrotizing mediastinitis and concomitant aspiration pneumonia were evident on the image studies. We performed video-assisted thoracoscopic surgery to achieve immediate and adequate drainage, and the patient resumed normal deglutition 2 months later. Early diagnosis and prompt video-assisted thoracoscopic surgery intervention are paramount to manage this life-threatening situation.

Peironimev-Plus® in the treatment of chronic inflammation of tunica albuginea (Peyronie's disease). results of a controlled study.

Peyronie's Disease (PD) is a connective tissue disorder involving the growth of fibrous plaques in penile corpora cavernosa (tunica albuginea). The conservative treatment is indicated in the development stage of PD for at least one year after diagnosis and in case of penile pain. This study was conducted to demonstrate the possible effectiveness of the new substances of Peironimev-plus®. Sixty four patients (age: 29-65 years, mean: 52.57 ± 9.06) diagnosed with PD were enrolled in a medical treatment. All patients underwent the following diagnostic tests: penile ultrasound, photographic documentation of penile curvature, IIEF questionnaire (erectile function score), pain evaluation with Visual Analogue pain Scale (VAS). The patients were divided into two treatment groups with different combinations of drugs: A = Peironimev-plus/oral/one tablet-daily + Verapamil injection (peri-lesional) 10 mg/every two weeks + Verapamil iontophoresis/5 mg/three times a week - for 6 months; B = Verapamil injection (peri-lesional) 10 mg/every two weeks + Verapamil iontophoresis/5 mg/three times a week - for 6 months. Intergroup analysis revealed statistically significant differences: in group A the effective plaque size reduction was -30.8% while in the group B the reduction was -18.0% (p=0.000). In group A the improvement of curvature occurred in 85.1% of the cases while in group B this occurred only in 53.5% (p=0.024), moreover the mean curvature decrease was respectively - 8.7° and - 4.6° (p=0.002). IIEF score was significantly improved in group A patients with erectile dysfunction (p=0.02). Our results suggest that Peironimev-plus is an effective drug in treating PD and it may help to prevent the progression of PD.

Fixed drug eruption to ingested propolis.

Fixed drug eruptions (FDEs) are a unique type of drug allergy in which skin lesions recur in the same location after each ingestion of the offending agent. More than 100 drugs have been implicated in causing FDEs. More recently, herbal medications and food additives have been implicated. Propolis is an important contact allergen, but has not previously been reported to cause FDE. We present the case of a patient with a 1-year history of a recurrent lesion on the shaft of his penis. He tested strongly positive to propolis and had been using a herbal supplement. A trial off this supplement was initiated, and his penile lesion cleared. The patient then rechallenged himself with his powder and developed the same reaction, biopsy-proven to be consistent with FDE. This case illustrates the utility of systemic (rechallenge) and topical (patch-testing) testing to identify the causative agent. It is interesting to note that our patient developed a reaction at the site of the patch test for propolis itself, rather than at the former reaction site. Our patient also illustrates the necessity of considering new causes for FDE when typical lesions are present.