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Allergic contact dermatitis to Aloe vera



We present the case of a 72-year-old woman observed for dermatitis on the legs followed by apperance of erythema on the eyelids. She had a past history of peripheral venous insufficiency and had been using self home-made Aloe vera juice over the legs for relief from pain. Patch tests showed positive reactions to the leaf of Aloe, the macerated Aloe jelly, and nickel sulfate. Although most manufacturers process Aloe products avoiding its irritant extracts, and probably as a consequence reports of allergic reactions are rare, one must remember that the growing popularity on the use of Aloe products may stimulate its use 'as is' by the patients. Furthermore, it is important to specifically ask patients about the use of these products, because they consider it as innocuous and thus would not spontaneously provide such information.
Allergic contact dermatitis to Aloe vera
Márcia Ferreira, Marta Teixeira, Elvira Silva, Manuela Selores
Contact Dermatitis, Volume 57, Issue 4, pages 278279, October 2007
We present the case of a 72-year-old woman observed for dermatitis on the legs followed by apperance of
erythema on the eyelids. She had a past history of peripheral venous insufficiency and had been using self
home-made Aloe vera juice over the legs for relief from pain. Patch tests showed positive reactions to the
leaf of Aloe, the macerated Aloe jelly, and nickel sulfate. Although most manufacturers process Aloe
products avoiding its irritant extracts, and probably as a consequence reports of allergic reactions are rare,
one must remember that the growing popularity on the use of Aloe products may stimulate its use ‘as is’ by
the patients. Furthermore, it is important to specifically ask patients about the use of these products,
because they consider it as innocuous and thus would not spontaneously provide such information.
Keywords: allergic contact dermatitis; Aloe vera; medicinal plants; sensitization
Aloe barbadensis (Miller), commonly referred as Aloe vera (‘aloe’ derived from the Arabic word ‘alloeh’
meaning ‘bitter and shiny substance’, and ‘vera’ from the Latin word for ‘truth’), native to the North African
and the Arabian peninsula is the most potent of the approximately 420 Aloe species and one of the most
widely used herbal products throughout the world. It contains pharmacologically active ingredients
advocated for the healing of several diseases. Despite its widespread use, reports of allergic reactions are
Case report
A 72-year-old woman was observed for a 3-month history of pruriginous erythema of the legs, followed by
intense itching, erythema, and desquamation of the eyelids (Figs 1 and 2). Shortly before, she had started
applying self home-made Aloe vera leaf juice over the legs for the treatment of chronic peripheral venous
insufficiency. There was no history of atopy or other relevant medical condition.
Figure 1: Mild unilateral swollen right leg. Mottled hyperpigmentation over the legs, erythema, and
desquamation predominantly affecting the lower third.
Figure 2.:Chronic dermatitis of the eyelids.
She was patch tested with the Portuguese Contact Dermatitis Group standard series (Chemotechnique,
Malmö, Sweden), Aloe jelly ‘as is’ (liquid extract from the macerated plant) and Aloe pulvis (the whole
macerated leave) ‘as is’, which were mounted on Finn Chambers (Scanpor Alpharma AS, Norgesplaster
Facility, Kristiansand, Norway) and fixed on the upper back with Mefix (Molnlycke Health Care, Götenborg,
Sweden). Her own hygiene personal products (bath gel and shampoo) were tested ‘as is’ semi-open: a
minute amount of the products were directly applied with a Q-tip on the skin, left to dry completely and
covered with Micropore® tape. The patch tests were removed after 2 days and test readings were recorded
1 day later, according to the International Contact Dermatitis Research Group terminology (1). Patch test
results showed positive reactions to Aloe jelly (++) and Aloe pulvis (++) ‘as is’ and to nickel sulfate (+) on
day 3, as summarized in Table 1. The Aloe extracts were applied in the same way on 20 volunteers; none
of them experienced an irritant or allergic reaction.
Table 1. Results of the patch tests on day 3
Day 3
Aloe jelly as is
Aloe pulvis as is
Nickel sulfate (5% pet.)
The application of Aloe was strongly dissuaded and topical costicosteroids were prescribed
(hydrocortisone 1% cream for the eyelids and methylprednisolone aceponate 0.1% ointment for the legs).
The lesions gradually improved with total resolution in 2 weeks, without recurrence in an 8-month follow-up
Aloe vera, used for several centuries, is a well-known medicinal plant belonging to the family Liliaceae.
Through human trade and migration, this plant came to be known and was widely used to cure burns and
wounds throughout ancient civilizations. Several supposed properties, such as potent anti-inflammatory,
antimicrobial and even anti-tumoral effects apply to its growing popularity, and nowadays it is advocated
for the healing of injuries, psoriasis, radiation dermatitis, and several other diseases. Besides this, Aloe is
believed to balance the pH of the skin and is therefore used in hundreds of medicines and over-the-
counter products such as shampoos, soaps, shaving creams, deodorants, sunscreens, and moisturizers
(2, 3). However, randomized double-blind casecontrol studies to quantify any benefits of Aloe as a
primary active ingredient are warranted.
Allergic contact dermatitis due to other Liliaceae, such as Allim and Tulipa are well known, but reactions
resulting from the application or intake of Aloe vera are extremely rare, mostly reported more than 15
years ago (4, 5). This might be explained by considering the 2 components of the plant: the bark of the
leaves containing antrachinones with a considerable irritant and allergic potential, and the pulp in the
centre of the leaves with high water content and carbohydrates. Nowadays, most manufacturers of Aloe
products process the Aloe gel from the centre of the leaves, avoiding the irritant extracts (6). Given the
rarity on recent reports of truly adverse cutaneous reactions and its widespread use, one can suppose that
the use of properly processed topical products containing Aloe vera is relatively safe.
In the case presented in this study, the sensitizing capacity of the plant ‘as is’ was shown by the induction
of an allergic contact dermatitis over the legs and the eyelids, in the later probably due to hand transfer. It
also reflects the growing popularity of the ‘so-called’ natural products, conducting to their uncontrolled use
and aware to the lack of effective regulation on these products.
Therefore, adverse effects of herbal medicines need to be suspected and investigated, as these are rare
but real causes of allergic contact dermatitis.
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McGovern T W. Dermatoses due to plants. In: Dermatology, 1st edition, BologniaJ L, JorizzoJ L, RapiniR
P, HornT D, MascaroJ M, ManciniA J, SalascheS J, SauratJ H, StinglG. Edinburgh, Mosby, 2003: 265
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Reider N, Issa A, Hawranek T, Schuster C, Aberer W, Kofler H, Fritsch P, Hausen B M. Absence of
contact sensitization to Aloe vera (L.) Burm. f. Contact Dermatitis 2005: 53: 332334.
... There have been reports of severe allergic reaction to homemade Aloe Vera gels which have not been purified from irritant compounds [68]. ...
Full-text available
Aloe Vera is a tender and succulent type of plant belonging to the Liliaceae family and genus Aloe. It has been used as a medicinal plant for its healing and soothing properties for more than 2000 years. Properties of the Aloe Vera are not only specie dependent but also on how it is handled after being collected. Due to the adverse effects associated with conventional drugs, researchers are again interested in pursuing plant-based therapies for diseases.
... As a type of laxative, the application of Aloe vera latex also resulted in functional damage, such as colorectal lesions and kidney dysfunction (Cholongitas et al., 2005;GORKOM et al., 1999). Although there were no severe adverse effects or carcinogenicity reported owing to the application of Aloe vera gel, the occurrence of allergy or hypersensitivity of skin might be an obstacle limiting the extensive use for this specific portion of it (Ferreira et al., 2007;Morrow et al., 1980). Overall, the current state of Aloe vera application is a controversial issue. ...
Ethnopharmacological relevance Aloe vera (L.) Burm. f. is a typical traditional Chinese medicine (TCM) collected in the Pharmacopoeia of the People's Republic of China (version 2015). It has been traditionally used for the treatment of constipation, and its potential therapeutic activities have been widely evaluated, including anti-tumor, anti-inflammatory and immune regulatory effects. The wide application of Aloe vera in food and therapy has raised safety issues and there are multiple safety assessments with a diverse toxicity and adverse effects from clinics and animals. Aim of the study This study aimed to investigate the safety of Aloe vera barbadensis extract C (AVBEC) in rats and analyze its anticancer activity in cell lines. Materials and methods We administrated AVBEC orally in an acute toxicity study and a 6-month chronic toxicity study to observe and confirm its safety in Sprague-Dawley (SD) rats. Additionally, we explored the cytotoxicity of AVBEC in cancer cells and non-cancer cells. We further investigate the anti-tumor activity of AVBEC, and in the meantime, probe the function of component from AVBEC. Results No deaths or substance-relative toxicity were observed in the acute toxic study or the 6-month chronic toxicity study with doses of 44.8 g·kg-1 and 4.48 g·kg-1, respectively. In the chronic toxicity study, AVBEC did not cause organ toxicity, including crucial organ structure and chemical function, and peripheral and central immune system damage. Additionally, we found that AVBEC could induce cancer cell apoptosis with a relatively higher apoptotic ratio than in non-cancer cells by decreasing adenosine triphosphate (ATP) concentration and enhancing reactive oxygen species (ROS) production. We also identified components in AVBEC using high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) and probed the function of malic acid. This demonstrated that under the same circumstances, malic acid induced cell necrosis in cancer cells and non-cancer cells, while AVBEC did not. Conclusions These results reveal a novel mechanism of aloe gel extract in regulating cancer cell apoptosis via modulating the mitochondrial metabolism and imply a possible application of AVBEC for the treatment of malignant cancer with the safety evaluation from rats and anticancer investigation from cancer cell and non-cancer cells.
... Patch test showed positive reactions to the leaf of Aloe, the macerated Aloe jelly, and nickel sulfate. [3] Hypersensitivity manifested by generalized nummular eczematous and papular dermatitis developed in a 47-year-old man after using oral and topical aloe. Patch tests for Aloe were positive. ...
... Aloe vera may cause a flush, burning, and tingling sensation or allergic reaction when used topically. [38] Allergic reactions are mostly occurred due to the presence of anthraquinones. [39] Three case reports of Aloe vera-induced toxic hepatitis have also been received. ...
Oral lichen planus Oral submucous fibrosis Recurrent aphthous stomatitis A B S T R A C T Background and aim: Aloe vera is also called Aloe barbadensis Miller. Aloe vera has been utilized for its numerous salutary properties. It has been utilized for fast wound healing and pain alleviation. There are few clinical studies recorded where Aloe vera is utilized in the treatment of oral mucosal diseases. The rationale for this review is to study clinical trials to assess the adequacy of Aloe vera in the treatment of oral mucosal diseases. Materials and methods: PubMed (Central), Wiley online library, Elsevier, Google scholar, and Hinary were used from the electronic databases using keywords until December 2020 to perform systematic literature. The quest was based on the terms of Mesh. Randomized or quasi-randomized clinical trials, cross-sectional and case-control studies included in this review. Literatures in English were only considered for this review. Review articles, experimental studies, and in-vitro studies were excluded in this review. Results: A total of 20 articles met the inclusion criteria. These articles were clinical trials for assessing the efficiency of Aloe vera in oral mucosal diseases that showed the efficacy of Aloe vera in oral submucous fibrosis, oral lichen planus, burning mouth syndrome, recurrent aphthous stomatitis, and chemotherapy-induced stomatitis. It showed fewer beneficial effects on radiation-induced mucositis. Conclusion: In the future, Aloe vera can play a promising role in various oral diseases. More studies should be performed in the future to determine the appropriate dose and effects on oral mucosal diseases. Evaluating possible side effects and long-term application of Aloe vera is also recommended.
... A 72-year-old patient presented with contact dermatitis on the legs and eyelids after the application of a home-made Aloe vera juice. Patch tests were positive to this plant (Ferreira et al., 2007). In addition, there were reports of a burning sensation of the skin in four patients after applying a preparation of Aloe vera gel in areas previously subjected to chemical or surgical beauty treatments (Hunter and Frumkin, 1991;Ernst, 2000). ...
Synonyms: Aloe barbadensis Mill., Aloe vulgaris Lam., Aloe perfoliata var. vera L. (Adams, 1972)
Objective: Aloe vera is a cost-effective, accessible wound care adjunct with a minimal risk profile. Despite its centuries-long history being used to treat varying wound types, published reports remain inconclusive on its efficacy. In this article, the authors report the results of a systematic review assessing the efficacy of topical aloe vera products in wound care applications, as well as a meta-analysis of its utility in burn healing where data are most robust. Data sources: In accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, the authors searched PubMed, EMBASE, and Cochrane CENTRAL for randomized controlled trials assessing the use of aloe vera in healing various wound types. Study selection: The database search identified 91 articles. After duplicates were removed, 74 articles were screened, and of those, 47 were assessed for eligibility. Ultimately, 28 articles were included in the qualitative synthesis, and 4 studies assessing second-degree burns were included in the meta-analysis. Data extraction: The following data points were collected from each study: number of participants/wounds, treatment type, adjunctive therapy (if any), and primary outcomes. Data synthesis: Risk-of-bias analysis was conducted on included articles, and results were compiled. A meta-analysis was undertaken for studies focusing on the treatment of burns. Cumulatively, these studies had a total of 133 patients with 163 wounds being assessed. Analysis revealed a statistically significant mean difference in time to healing of 4.44 days in favor of aloe vera treatment (P = .004). Conclusions: Topical aloe vera usage for second-degree burn wound healing demonstrated significantly faster time to healing compared with other treatments.
Background Aloe vera is a functional food with various pharmacological functions, including an immune-modulating effect. Until now, A. vera has never been studied as an adjuvant in influenza vaccine, and its effects on upper respiratory tract infection (URI) are unknown. Purpose The objective of our study was to investigate the effect of processed A. vera gel (PAG) on immunogenicity of quadrivalent inactivated influenza vaccine and URI in healthy adults. Study design A randomized, double-blind, placebo-controlled clinical trial was performed. Methods This study was conducted in 100 healthy adults at a single center from September 2017 to May 2018. Subjects were randomly divided into a PAG group (n = 50) and a placebo group (n = 50). The enrolled subjects were instructed to ingest the study drug for 8 weeks. The participants received a single dose of quadrivalent inactivated influenza vaccine after taking the study drug for the first 4 weeks of the study. The primary endpoint was seroprotection rate against at least one viral strain at 4 weeks post-vaccination. Other outcomes were seroprotection rate at 24 weeks post-vaccination, seroconversion rate, geometric mean fold increase (GMFI) at 4 and 24 weeks post-vaccination, seroprotection rate ratio and geometric mean titer ratio (GMTR) at 4 weeks post-vaccination between PAG and placebo groups, and incidence, severity, and duration of URI. Results The European Committee for proprietary medicinal products (CPMP) evaluation criteria were met at least one in the PAG and placebo groups for all strains. However, there was no significant difference in the seroprotection rate at 4 weeks post-vaccination against all strains in both PAG and placebo groups. Among secondary endpoints, the GMFI at 4 weeks post-vaccination for the A/H3N2 was significantly higher in the PAG than in placebo group. The GMTR as adjuvant effect was 1.382 (95% CI, 1.014-1.1883). Kaplan–Meier curve analysis showed a reduction in incidence of URI (p = 0.035), and a generalized estimating equation model identified a decrease in repeated URI events (odds ratio 0.57; 95% CI, 0.39-0.83; p = 0.003) in the PAG group. Conclusions Oral intake of PAG did not show a significant increase in seroprotection rate from an immunogenicity perspective. However, it reduced the number of URI episodes. A well-designed further study is needed on the effect of PAG's antibody response against A/H3N2 in the future.
Aloe vera is one of the few edible species in the genus Aloe, and its products are widely used in foods, cosmetics, health care products, medicines and other fields. Barbaloin is the highest content of anthraquinones in aloe, which has potential allergenicity, and it is one of the important indicators for the quality control of aloe-containing products. Aiming at resolving the problems of barbaloin instability, easy sensitization and high residue, the transformation and degradation mechanisms of barbaloin under different processing conditions (temperature, pH, food additives and metal ions) were studied in this research, and the toxicity of the products were evaluated. The results showed that the transformation and degradation of barbaloin can be significantly accelerated by high temperature, alkaline conditions, calcium chloride, carboxymethyl cellulose, Fe³⁺ and Mg²⁺ (p < 0.001). However, they can be significantly inhibited by the acidic environment and Pb²⁺ (p < 0.001). And the transformation and degradation of barbaloin in aloe powder were almost the same as those in the barbaloin aqueous solution. The main transformation and degradation products of barbaloin were isobarbaloin, aloe emodin, 10-Hydroxyalloin A and 10-Hydroxyalloin B, and the other two unknown products were isomers. And aloe emodin may have greater toxicity hazards and potential safety risks. The molecular electrostatic potential properties also indicated that the 10th carbon atom of barbaloin, isobarbaloin, 10-Hydroxyaloin A and 10-Hydroxyaloin B may be more likely to break chemical bonds and generate new transformation and degradation products. These research results can be applied to the control of barbaloin and aloe emodin in the processing of aloe-containing products, so as to provide the basis for the better development and utilization of aloe.
Psoriasis is a chronic, inflammatory, multisystem disease which affects up to 3.2% of the U.S population. This guideline addresses important clinical questions that arise in psoriasis management and care and provides recommendations based on the available evidence. The treatment of psoriasis with topical agents and with alternative medicine (AM) will be reviewed, emphasizing treatment recommendations and the role of dermatologists in monitoring and educating patients regarding benefits as well as risks that may be associated. This guideline will also address the severity assessment methods of psoriasis in adults.
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Here we report that aloe-emodin (AE), a hydroxyanthraquinone pres- ent in Aloe vera leaves, has a specific in vitro and in vivo antineuroecto- dermal tumor activity. The growth of human neuroectodermal tumors is inhibited in mice with severe combined immunodeficiency without any appreciable toxic effects on the animals. The compound does not inhibit the proliferation of normal fibroblasts nor that of hemopoietic progenitor cells. The cytotoxicity mechanism consists of the induction of apoptosis, whereas the selectivity against neuroectodermal tumor cells is founded on a specific energy-dependent pathway of drug incorporation. Taking into account its unique cytotoxicity profile and mode of action, AE might represent a conceptually new lead antitumor drug.
A 66-Year-old Japanese male with allergic contact dermatitis to Aloe arborescens Mill var. natalensis had generalized nummular and papular dermatitis after 20 days use of topical aloe jelly. Patch testing with aloe jelly a strong reaction in the patient, but was negative in 8 controls.
Aloe vera has been used as a cosmetic and medical remedy since ancient times and has gained increasing popularity in recent years. Despite its widespread use, reports of allergic reactions are rare. We patch tested 702 consecutive patients with an oily extract from the leaves, Aloe pulvis from the entire plant and concentrated Aloe vera gel. A specially designed questionnaire was used for the use of Aloe vera, reasons and location of application, adverse reactions, occupation, hobbies and atopy. None of the subjects showed any reaction to one of the preparations. 2 components of the plant have to be distinguished: the bark of the leaves contains anthrachinones with pro-peristaltic and potential antibiotic and anticancer properties. Constraints have been imposed due to their considerable toxic potential. Today, mostly the Aloe gel from the center of the leaves is processed. It almost exclusively consists of carbohydrates to which also many medical effects have been attributed. Carbohydrates are not likely to induce contact sensitization, which might explain the outcome of our study. However, this does not justify unrestrained promotion of Aloe products, as scientific studies investigating the claims on its constitutional effects are few in number, and the majority of them have been unable to diminish the intuitive scepticism against miracle cures, like Aloe seems to be.
Aloe barbadensis (Miller), Aloe vera, has a long history of use as a topical and oral therapeutic. The plant is the source of two products, gel and latex, which are obtained from its fleshy leaves. Aloe vera products contain multiple constituents with potential biological and toxicological activities, yet the active components elude definition. Ingestion of Aloe vera is associated with diarrhea, electrolyte imbalance, kidney dysfunction, and conventional drug interactions; episodes of contact dermatitis, erythema, and phototoxicity have been reported from topical applications. This review examines the botany, physical and chemical properties, and biological activities of the Aloe vera plant.
Dermatoses due to plants
  • T W Mcgovern
  • L Bologniaj
  • Rapinir L P Jorizzoj
  • D Hornt
  • M Mascaroj
  • J Mancinia
  • J Salasches
  • Sauratj
McGovern T W. Dermatoses due to plants. In: Dermatology, 1st edition, BologniaJ L, JorizzoJ L, RapiniR P, HornT D, MascaroJ M, ManciniA J, SalascheS J, SauratJ H, StinglG. Edinburgh, Mosby, 2003: 265– 283.