Chapter 24 Treatment of Allergies PDF

Chapter 24 Treatment of Allergies Copyright © 2019 by Elsevier, Inc. All rights reserved.  Lesson 24.1 Treatment of Allergies 1. Learn the terminology associated with allergies. 2. Describe the causes and list the symptoms of allergic reactions. 3. List and categor...

Chapter 24 Treatment of Allergies Copyright © 2019 by Elsevier, Inc. All rights reserved.  Lesson 24.1 Treatment of Allergies 1. Learn the terminology associated with allergies. 2. Describe the causes and list the symptoms of allergic reactions. 3. List and categorize medications used in the treatment of allergies. 4. Describe the mechanism of action for drugs used to treat allergies. 5. Identify significant drug look-alike/sound-alike issues. 6. Identify warning labels and precautionary messages associated with medications used for the treatment of allergies. Copyright © 2019 by Elsevier, Inc. All rights reserved. 2  Key Terms  Chapter Key Terms Review Copyright © 2019 by Elsevier, Inc. All rights reserved. 3  Overview  Allergy: Hypersensitivity reaction by immune system 40 and 50 million people in the United States  Seasonal allergic rhinitis: Seasonal pollens Up to 20% of U.S. population Copyright © 2019 by Elsevier, Inc. All rights reserved. 4  What Triggers an Allergic Response?  Exposure to allergen  Immune system treats allergen as an invader and produces antibodies: Engineered by T lymphocytes- CD4+, CD8+, T cells Antibodies (IgE) are formed IgE attach to mast cells, which contain histamine  Histamine is released to produce symptoms wheezing, rash, runny nose, itching Copyright © 2019 by Elsevier, Inc. All rights reserved. 5  Poll question 1 Copyright © 2019 by Elsevier, Inc. All rights reserved. 6  Symptoms of allergy  Localized or generalized  Allergic shiners (dark circles under the eyes caused by increased blood flow near the sinuses)  Allergic salute (a crease across the bridge of the nose caused by persistent upward rubbing of the nose) Copyright © 2019 by Elsevier, Inc. All rights reserved. 7  Other Symptoms of Allergies DERMAL RESPIRATORY  Itchy eyes, nose, and throat  Runny nose  Stuffy nose Rash  Sneezing  Coughing Redness  Watery eye  Conjunctivitis Urticaria 8  Urticaria  AKA Hives  Symptoms Itching Angioedema Redness Swelling Wheals (blister-like vesicles)  Causes insect bite, drug or food allergy, or injection of allergen extracts (allergy shots). Copyright © 2019 by Elsevier, Inc. All rights reserved. 9  Urticaria treatment  Usually self limiting  Severe urticaria Antihistamines Glucocorticosteroids  Acute pharyngeal or laryngeal angioedema Rapidly reduce swelling in the throat Restore breathing Use short-acting beta2-adrenergic agonists Copyright © 2019 by Elsevier, Inc. All rights reserved. 10  Allergic Rhinitis  Nasal itching, runny nose, nasal congestion, and sneezing  Caused by inflammation and swelling of the nasal passageways  May be perennial or seasonal  Symptoms appear after a period of absence from allergen exposure  Recurs seasonally due to presence of memory CD4+ T cells: Allergen specific antibodies (tree, grass, pollen)  Usually self limiting Copyright © 2019 by Elsevier, Inc. All rights reserved. 11  Allergic Conjunctivitis  Red, watering, itchy, or burning eyes  Ocular puffiness and stringy discharge  May be seasonal  Worsen during allergy and hay fever season  Typically self-limiting  Decongestants use may cause Conjunctivitis medicamentosa- rebound redness and congestion Copyright © 2019 by Elsevier, Inc. All rights reserved. 12  Occupational Allergens  Latex proteins: Disposable gloves, IV tubing and bag ports, syringes, catheters, injection ports, and rubber tops on vials  May become airborne and then inhaled  Dermal or respiratory symptoms  Perfumes or scents Copyright © 2019 by Elsevier, Inc. All rights reserved. 13  Drugs Used in the Treatment of Allergies  Antihistamines  Inhaled corticosteroids  Mast cell stabilizers  Leukotriene receptor agonists  Vasoconstrictors Copyright © 2019 by Elsevier, Inc. All rights reserved. 14  H1 Receptor Antagonists (1 of 2)  Several classes of antihistamines: Ethylenediamines Phenothiazines Phthalazinone Azelastine Piperidines Desloratadine Loratadine Fexofenadine Copyright © 2019 by Elsevier, Inc. All rights reserved. 15  H1 Receptor Antagonists ( 2 of 2)  Ethanolamines: Diphenhydramine Clemastine  Alkylamines: Brompheniramine Chlorpheniramine  Piperazine: Cetirizine Copyright © 2019 by Elsevier, Inc. All rights reserved. 16  Antihistamines  First generation Diphenhydramine, chlorpheniramine, hydroxyzine, brompheniramine  Second generation Cetirizine, levocetirizine, loratadine, desloratadine, and fexofenadine Copyright © 2019 by Elsevier, Inc. All rights reserved. 17  H1 Receptor Antagonists: MOA  Prevents histamine binding to H1 receptor sites: Drugs compete with free histamine for binding  Half-life varies from short (4 to 6 hours) to long (24 hours)  Hydroxyzine metabolizes to Cetirizine Copyright © 2019 by Elsevier, Inc. All rights reserved. 18  Antihistamines Adverse effects  Decreased alertness  Sedation (most with diphenhydramine and promethazine)  Dizziness  Dry mouth  Blurred vision  Urinary retention Copyright © 2019 by Elsevier, Inc. All rights reserved. 19  Precautions  Use with caution in men with prostate disease Women who are breastfeeding  Not recommended for children under 2 years Copyright © 2019 by Elsevier, Inc. All rights reserved. 20  Warning Labels: H1 Receptor Antagonists (1 of 2)  May cause drowsiness; alcohol may increase this effect (ethanolamines, alkylamines, and piperazines)  Swallow whole; don’t crush or chew (extended release)  May cause dizziness or drowsiness Copyright © 2019 by Elsevier, Inc. All rights reserved. 21  Warning Labels: H1 Receptor Antagonists (2 of 2)  Protect from moisture; leave in foil packet until ready to use (disintegrating tablets)  Dissolve reditab under the tongue (disintegrating tablets)  Avoid orange, grapefruit, and apple juice (fexofenadine)  Prime inhaler before use Copyright © 2019 by Elsevier, Inc. All rights reserved. 22  Look-Alike/Sound-Alike Drugs  Diphenhydramine and dimenhydrinate  Allegra and Viagra  Zyrtec, Zantac, Xanax, and Serax  Claritin and Clarinex Copyright © 2019 by Elsevier, Inc. All rights reserved. 23  Glucocorticosteroids Intranasal  Beclomethasone  Budesonide  Flunisolide  Fluticasone propionate and fluticasone furoate  Triamcinolone  Mometasone Copyright © 2019 by Elsevier, Inc. All rights reserved. 24  Glucocorticosteroids: MOA  Inhibit onset of inflammatory response: Reduce permeability of nasal mucosa cells to T lymphocytes and eosinophils Decreasing release of mediators of inflammatory response  Reduce the number of inflammatory cells: Reduction in mucus and swelling Copyright © 2019 by Elsevier, Inc. All rights reserved. 25  Glucocorticosteroids: Adverse Reactions  Nasal burning or stinging  Throat irritation  Nose bleed  Nasal Candida infection Copyright © 2019 by Elsevier, Inc. All rights reserved. 26  Poll question 2 Copyright © 2019 by Elsevier, Inc. All rights reserved. 27  Look-Alike/Sound-Alike Drugs  Flunisolide and fluocinonide  Nasarel, Nasacort, and Nasalide  Fluticasone propionate and fluticasone furoate  Flonase and Flovent Copyright © 2019 by Elsevier, Inc. All rights reserved. 28  Mast Cell Stabilizers  Cromolyn sodium (Opticrom, Rhinaris)  Nedocromil (Alocril)  Intranasal and ophthalmic use  Reduces reactivity to allergens: Decreases mast cell degranulation Decrease release of inflammatory substances  Not useful for acute symptoms Copyright © 2019 by Elsevier, Inc. All rights reserved. 29  Mast Cell Stabilizers: Adverse Reactions  Unpleasant taste  Dry throat, cough  Difficulty breathing  Headache  Nose bleeds  Runny nose, sneezing  Stinging, burning, or irritation inside the nose Copyright © 2019 by Elsevier, Inc. All rights reserved. 30  Leukotriene Receptor Antagonists  Montelukast: Controls allergic rhinitis symptoms Selective antagonist of the cysteinyl leukotriene D4 receptor Copyright © 2019 by Elsevier, Inc. All rights reserved. 31 Leukotriene Receptor Antagonists: Adverse Reactions  Cough, hoarseness, or sore throat  Headache  Indigestion, heartburn, or stomach upset  Runny nose  Difficulty sleeping  Dizziness  Drowsiness  Muscle aches or cramps  Unusual dreams Copyright © 2019 by Elsevier, Inc. All rights reserved. 32  Immunotherapy  Allergy shots: Administered via subcutaneous injection For perennial or seasonal allergies Reduce the levels of IgE Stimulate the production of IgG Administered as a series: Each injection has an increased concentration of the allergen that produces sensitivity Copyright © 2019 by Elsevier, Inc. All rights reserved. 33  Angioedema  Self-limited, localized subcutaneous (or submucosal) swelling, Results from extravasation of fluid into interstitial tissues.  Mostly affects loose connective tissue Face, lips, mouth, and throat, larynx, uvula, extremities, and genitalia.  Two types Mast cell-mediated or histaminergic angioedema Bradykinin-mediated angioedema Copyright © 2019 by Elsevier, Inc. All rights reserved. 34  Treatment of Angioedema  If near the airways Intubation  With anaphylaxis Epinephrine, O2 and IV fluids  With Acute allergic reactions Antihistamines or glucocorticoids  ACEi induced- Remove medication, replace with ARB is appropriate Copyright © 2019 by Elsevier, Inc. All rights reserved. 35  Anaphylaxis  Acute, potentially life-threatening, systemic hypersensitivity reaction Caused by the sudden release of mast cell mediators Immunoglobulin E (IgE)-mediated reactions to foods, drugs, and insect stings, or any agent capable of inciting a sudden, systemic degranulation of mast cells  Severity ranges from self-limiting mild to fatal - death Copyright © 2019 by Elsevier, Inc. All rights reserved. 36  Signs and symptoms  Skin and mucosal symptoms- Hives, itching or flushing, swollen lips-tongue-uvula, periorbital edema, or conjunctival swelling.  Respiratory symptoms and signs, nasal discharge, nasal congestion, sneezing, itching of the throat and ear canals, change in voice quality, sensation of throat closure or choking, stridor, shortness of breath, wheeze, or cough. . Copyright © 2019 by Elsevier, Inc. All rights reserved. 37  Signs and symptoms  Gastrointestinal symptoms and signs nausea, vomiting, diarrhea, and crampy abdominal pain.  Cardiovascular symptoms and signs hypotonia (collapse), syncope, incontinence, dizziness, tachycardia, and hypotension Copyright © 2019 by Elsevier, Inc. All rights reserved. 38  Emergency management  Removal of the inciting cause (medication or allergen)  Call for help  Intramuscular (IM) injection of epinephrine and PRN (EpiPen or IV Epinephrine)  Supplemental oxygen  Volume resuscitation with IV fluids Copyright © 2019 by Elsevier, Inc. All rights reserved. 39  Poll question 3 Copyright © 2019 by Elsevier, Inc. All rights reserved. 40  Questions? Copyright © 2019 by Elsevier, Inc. All rights reserved. 41