Related Experiment Video
Updated: Jul 19, 2026
08:25
Contact Hypersensitivity as a Murine Model of Allergic Contact Dermatitis
Published on: September 26, 2022
Probable cutaneous allergic response to subcutaneous heparin--a case report
1Department of dermatology and venereal disease, Manipal Teaching Hospital/Manipal College of Medical Sciences Pokhara, Nepal. babitasanjeev@yahoo.com
Acta Dermatovenerologica Alpina, Pannonica, Et Adriatica
|September 26, 2006
Summary
Heparin, a common anticoagulant, can cause delayed skin reactions like eczema and tissue necrosis even after treatment stops. Patient counseling is crucial due to these potential adverse events.
Area of Science:
- Pharmacology
- Dermatology
- Immunology
Background:
- Heparin is a widely used injectable anticoagulant derived from sulfated mucopolysaccharides.
- Cutaneous adverse reactions, including eczema, erythematous plaques, exfoliative dermatitis, and tissue necrosis, are known side effects of heparin therapy.
Observation:
- This report details a case of a probable cutaneous allergic response to heparin injection.
- The reaction's causality and severity were established.
- The adverse event manifested after heparin therapy was discontinued and the patient had been discharged.
Findings:
- A delayed-onset cutaneous allergic reaction to heparin was observed.
- The reaction occurred post-cessation of heparin treatment.
Implications:
- Given heparin's widespread use and the potential for delayed reactions, comprehensive patient education is essential.
- Healthcare providers must counsel patients on the possibility of adverse skin reactions occurring even after stopping heparin therapy.
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...
01:19Hypersensitivity 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...
01:30Allergic 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),...
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
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...
01:29Hypersensitivity Reactions: Delayed Hypersensitivity Reactions
Delayed-Type Hypersensitivity (DTH), or Type IV hypersensitivity, is a cell-mediated immune response. It occurs when T cells, rather than antibodies, mediate a reaction to specific antigens. It is characterized by a delayed onset (1-2 days) and involves the recruitment of macrophages to the inflammation site.The initiation of a DTH response begins with the sensitization of T cells. During this phase, which lasts at least 1-2 weeks, antigen-specific T cells are activated, clonally expanded, and...