Related Experiment Video
Updated: Jul 11, 2026
08:02
A Mouse Ear Model for Allergic Contact Dermatitis Evaluation
Published on: March 24, 2023
Allergic contact dermatitis to Aloe vera.
Márcia Ferreira1, Marta Teixeira, Elvira Silva
1Department of Dermatology, Hospital Geral de Santo António, Porto, Portugal. marcia_ferreira@hotmail.com
Contact Dermatitis
|September 18, 2007
Summary
This case study highlights potential allergic reactions to homemade Aloe vera juice, emphasizing the need for patient disclosure of its use. It underscores that even natural remedies can cause adverse skin reactions like dermatitis and erythema.
Area of Science:
- Dermatology
- Allergology
- Phytotherapy
Background:
- Aloe vera is widely used for its purported therapeutic properties.
- Patient self-treatment with natural products is common.
- Peripheral venous insufficiency can cause leg discomfort.
Observation:
- A 72-year-old woman developed leg dermatitis and eyelid erythema.
- She applied homemade Aloe vera juice to her legs for pain relief.
- Patch testing revealed allergies to Aloe vera components and nickel sulfate.
Findings:
- Positive patch test reactions confirmed allergy to raw Aloe vera leaf and jelly.
- The patient's symptoms were likely triggered by direct application of unprocessed Aloe vera.
- Nickel sulfate also elicited a positive reaction, suggesting co-sensitization or a separate allergy.
Implications:
- Homemade or unprocessed Aloe vera products may contain irritants causing allergic contact dermatitis.
- Healthcare providers should inquire about the use of natural remedies like Aloe vera.
- Increased popularity of Aloe vera necessitates awareness of potential adverse reactions, even from seemingly innocuous sources.
Related Concept Videos
01:30Drug Toxicity: Allergic Reactions
Drug-related allergies are immune-mediated responses triggered by the administration of pharmacological agents. These hypersensitivity reactions are classified based on the immune mechanisms involved. The four primary types—Type I, II, III, and IV—are mediated by different immunological pathways and exhibit distinct clinical manifestations.Type I Hypersensitivity/ IgE-Mediated Reactions: Immunoglobulin E (IgE) immediately mediates Type I hypersensitivity reactions. Upon initial exposure to a...
01:30Allergic Reactions: Anaphylaxis
Anaphylaxis is a severe, life-threatening hypersensitivity reaction mediated by Immunoglobulin E (IgE) antibodies. When IgE binds to allergens, it triggers the release of mediators– histamine, leukotrienes, and prostaglandins from mast cells and basophils. These mediators cause vasodilation, edema, and inflammation, leading to various symptoms.The primary allergens causing anaphylaxis include food items (e.g., peanuts, shellfish), drugs (e.g., penicillin, asparaginase, corticotropin, heparin),...
02:06Allergic Reactions
Overview
01:27Allergic Drug Reactions
Allergic reactions related to drugs are hypersensitivity responses driven by the immune system and bear no connection to the drug's therapeutic action. While drugs in isolation do not trigger an immune response, they can interact with endogenous proteins to form antigens. These antigens stimulate lymphocytes to produce antibodies. IgE-type antibodies attach themselves to mast cells. Upon subsequent exposure to the same stimulus, the antigen-antibody interaction is initiated, unleashing numerous...
01:19Hypersensitivity Reactions: Immune-Complex Reactions
Type III hypersensitivity reactions occur when antigen–antibody complexes form and activate the complement system. Normally, these complexes help the clearance of antigens by phagocytes and red blood cells. However, when large numbers of immune complexes are present, they can deposit in tissues—particularly in the walls of blood vessels—leading to inflammation and tissue injury. These deposits trigger complement activation and neutrophil recruitment, resulting in serum sickness, a systemic...
01:30Hypersensitivities
Hypersensitivity, also known as a hypersensitivity reaction or allergic reaction, is a condition where the body's immune system reacts abnormally to a foreign substance. Such substances, that cause hypersensitivity are referred to as an allergen, could be something typically harmless to most people, like pollen or certain foods.
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...