This document discusses different types of allergic reactions and allergic disorders. It outlines 5 types of hypersensitivity or allergic reactions including type 1 rapid reactions, type 2 cytotoxic reactions, type 3 immune complex mediated reactions, type 4 delayed hypersensitivity reactions, and type 5 stimulatory reactions. It then describes several allergic disorders like anaphylaxis, allergic rhinitis, contact dermatitis, atopic dermatitis, dermatitis medicamentosa, urticaria, and serum sickness. For each condition it provides details on symptoms, diagnosis, management, and supportive care.

1. ALLERGIC REACTIONS
Hypersensitivity/allergic responses- an increased or excessive response to the presence of an antigen to
which the client has been previously exposed
Type1: Rapid hypersensitivity reactions
- Reaction of IgE antibody on the mast cells with antigen, which results in the relase of mediators,
especially histamine
- Can be contacted in the following ways:
o Inhaled- plant pollen, fungal spores, animal dander, house dust, grass, ragweed)
o Infested- food, food additives, drugs
o Injected- bee venom, drugs, biologic substances such as dyes and adrenocorticotropic
hormone
- Contracted- pollens, foods, environmental proteins
Type 2: Cytotoxic- reaction of IgG with host cell membrane or antigen absorbed by host cell membrane
- Examples: Autoimmune hemolytic anemia
- Goodpasture’s syndrome
- Hemolytic transfusion reaction
Type 3: Immune complex-mediated
- Formation of immune complex of antigen and antibody, which results in complement release
and inflammation
- Examples: serum sickness, vasculitis, SLE, rheumatoid arthritis
Type 4: delayed hypersensitivity reactions
- Reaction of sensitized T-cells with antigen and release of lymphokines, which activate
macrophages and induce inflammation
- Examples: poison ivy, graft rejection, positive TB skin tests, sarcoidosis
Type 5: stimulatory reactions
- Reaction of autoantibodies with normal cell-surface receptors, which stimulates a continual
overreaction of the target cell
- Ex: Grave’s dse, B-cell Gammopathies
ALLERGIC DISORDERS

2. ANAPHYLAXIS- results from type1 in w/c release of chemical mediators from mast cells result in massive
vasodilation, increased capillary permeability
- Loss of consciousness, hives, swelling of tongues and throat tissues, inability to swallow,
difficulty breathing, low BP
- CxMx- uneasiness, apprehension, weakness, generalized itching, urticaria
- Intvns: tourniquet, CPR, O2, epinephrine, antihistamine, bronchodilators, steroids, strict IV
regulations
ALLERGIC RHINITIS- inflammation of the nasal mucosa caused by an allergen
- Dx: inc eosinophil in nasal smear
o Skin testing confirms hypersensitivity to specific allergen
o Radioallergosorbent test
- Mgt: antihistamines, topical or oral decongestants, intranasal cromolyn sodium, corticosteroids
intranasally or orally, immunotherapy
- Supportive care: reassure patient that suffocation will not occur
o Use bedside humidifier and inc fluid intake
o Observe pt after immunotherapy injection for 30mins for reaction
- Health maintenance- nasal inhalers, OTC decongestants to 2-3days only
DERMATITIS
Contact dermatitis- acute or chronic rash caused by either direct contact with an irritant substance or by
contact with an allergen
ATOPIC DERMATITIS- chronic rash that occurs with respi allergies and atopic skin dse
DERMATITIS MEDICAMENTOSA- drug reactions
Mgt: avoidance therapy, steroids
- Avoid applying oil-based products to sweaty skin folds; favourably used
- Corticosteroids never cure
- Antihistamines
- Compresses and baths
- Colloidal oatmeal preparations, tar extracts, cornstarch or oils are often added to baths to
relieve itching
URTICARIA
SERUM SICKNESS
- Caused by a collection of immune complexes deposited in the skin, joints and kidney

3. - Less common now because vaccines are made with human protein
- Causative agents: antilymphocyte globulin
- Interventions: symptomatic tx, antihistamine, aspirin, prednisone
LATEX ALLERGY