Allergy medical therapy

Jump to: navigation, search

Allergy Microchapters

Home

Patient Information

Overview

Historical Perspective

Pathophysiology

Causes

Differentiating Allergies from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

History and Symptoms

Physical Examination

Laboratory Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Allergy medical therapy On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Allergy medical therapy

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Allergy medical therapy

CDC on Allergy medical therapy

Allergy medical therapy in the news

Blogs on Allergy medical therapy

Directions to Hospitals Treating Allergies

Risk calculators and risk factors for Allergy medical therapy

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Treatment for allergic response is primarily pharmacotherapeutic. Common methodologies include immunotherapy via desensitization or hyposensitization, enzyme potentiated desensitization.

Medical Therapy

There have been enormous improvements in the medical treatments used to treat allergic conditions. With respect to anaphylaxis and hypersensitivity reactions to foods, drugs, and insects and in allergic skin diseases, advances have included the identification of food proteins to which IgE binding is associated with severe reactions and development of low-allergen foods, improvements in skin prick test predictions; evaluation of the atopy patch test; in wasp sting outcomes predictions and a rapidly disintegrating epinephrine tablet, and anti-IL-5 for eosinophilic diseases.[1]

Traditionally treatment and management of allergies involved simply avoiding the allergen in question or otherwise reducing exposure. For instance, people with cat allergies were encouraged to avoid them. While avoidance may help to reduce symptoms and avoid life-threatening anaphylaxis, it is difficult to achieve for those with pollen or similar air-borne allergies. Strict avoidance still has a role in management though, and is often used in managing food allergies.

Pharmacotherapy

Several antagonistic drugs are used to block the action of allergic mediators, or to prevent activation of cells and degranulation processes. These include antihistamines, cortisone, dexamethasone, hydrocortisone, epinephrine (adrenaline), theophylline and cromolyn sodium. Anti-leukotrienes, such as Montelukast (Singulair) or Zafirlukast (Accolate), are FDA approved for treatment of allergic diseases. Anti-cholinergics, decongestants, mast cell stabilizers, and other compounds thought to impair eosinophil chemotaxis, are also commonly used. These drugs help to alleviate the symptoms of allergy, and are imperative in the recovery of acute anaphylaxis, but play little role in chronic treatment of allergic disorders.

ANTIHISTAMINES

Antihistamines are available over-the-counter and by prescription. They are available in many forms, including:

CORTICOSTEROIDS

Anti-inflammatory medications (corticosteroids) are available in many forms, including:

Patients with severe allergic symptoms may be prescribed corticosteroid pills or injections for short periods of time.

DECONGESTANTS

Decongestants can help relieve a stuffy nose. Decongestant nasal spray should not be used for more than several days, because they can cause a "rebound" effect and make the congestion worse. Decongestants in pill form do not cause this problem.

OTHER MEDICINES

Leukotriene inhibitors are medicines that specifically block the substances that trigger allergies. Zafirlukast (Accolate) and montelukast (Singulair) are approved for those with asthma and indoor and outdoor allergies.

Immunotherapy

Desensitization or hyposensitization is a treatment in which the patient is gradually vaccinated with progressively larger doses of the allergen in question. This can either reduce the severity or eliminate hypersensitivity altogether. It relies on the progressive skewing of IgG antibody production, to block excessive IgE production seen in atopys. In a sense, the person builds up immunity to increasing amounts of the allergen in question. Studies have demonstrated the long-term efficacy and the preventive effect of immunotherapy in reducing the development of new allergy.[2] Meta-analyses have also confirmed efficacy of the treatment in allergic rhinitis in children and in asthma. A review by the Mayo Clinic in Rochester confirmed the safety and efficacy of allergen immunotherapy for allergic rhinitis and conjunctivitis, allergic forms of asthma, and stinging insect based on numerous well-designed scientific studies.[3] Additionally, national and international guidelines confirm the clinical efficacy of injection immunotherapy in rhinitis and asthma, as well as the safety, provided that recommendations are followed.[4]

A second form of immunotherapy involves the intravenous injection of monoclonal anti-IgE antibodies. These bind to free and B-cell associated IgE; signalling their destruction. They do not bind to IgE already bound to the Fc receptor on basophils and mast cells, as this would stimulate the allergic inflammatory response. The first agent of this class is Omalizumab. While this form of immunotherapy is very effective in treating several types of atopy, it should not be used in treating the majority of people with food allergies.

A third type, Sublingual immunotherapy, is an orally-administered therapy which takes advantage of oral immune tolerance to non-pathogenic antigens such as foods and resident bacteria. This therapy currently accounts for 40 percent of allergy treatment in Europe. In the United States, sublingual immunotherapy is gaining support among traditional allergists and is endorsed by doctors who treat allergy.

Unproven or Ineffective Treatments

An experimental treatment, enzyme potentiated desensitization (EPD), has been tried for decades but is not generally accepted as effective.[5] EPD uses dilutions of allergen and an enzyme, beta-glucuronidase, to which T-regulatory lymphocytes are supposed to respond by favouring desensitization, or down-regulation, rather than sensitization. EPD has also been tried for the treatment of autoimmune diseases but again is not FDA approved or of proven effectiveness.[5]

In alternative medicine, a number of allergy treatments are described by its practitioners, particularly naturopathic, herbal medicine, homeopathy, traditional Chinese medicine and kinesiology. Systematic literature searches conducted by the Mayo Clinic through 2006, involving hundreds of articles studying multiple conditions, including asthma and upper respiratory tract infection showed no effectiveness of any alternative treatments, and no difference compared with placebo. The authors concluded that, based on rigorous clinical trials of all types of homeopathy for childhood and adolescence ailments, there is no convincing evidence that supports the use of alternative treatments.[6]

References

  1. Sicherer SH, Leung DY (2007). "Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects". J. Allergy Clin. Immunol. 119 (6): 1462–9. doi:10.1016/j.jaci.2007.02.013. PMID 17412401.
  2. Ross RN, Nelson HS, Finegold I (2000). "Effectiveness of specific immunotherapy in the treatment of allergic rhinitis: an analysis of randomized, prospective, single- or double-blind, placebo-controlled studies". Clinical therapeutics. 22 (3): 342–50. doi:10.1016/S0149-2918(00)80038-7. PMID 10963288.
  3. Rank MA, Li JT (2007). "Allergen immunotherapy". Mayo Clin. Proc. 82 (9): 1119–23. PMID 17803880. Unknown parameter |month= ignored (help)
  4. Passalacqua G, Durham SR (2007). "Allergic rhinitis and its impact on asthma update: allergen immunotherapy". J. Allergy Clin. Immunol. 119 (4): 881–91. doi:10.1016/j.jaci.2007.01.045. PMID 17418661.
  5. 5.0 5.1 Terr AI (2004). "Unproven and controversial forms of immunotherapy". Clinical allergy and immunology. 18: 703–10. PMID 15042943.
  6. Altunç U, Pittler MH, Ernst E (2007). "Homeopathy for childhood and adolescence ailments: systematic review of randomized clinical trials". Mayo Clin. Proc. 82 (1): 69–75. PMID 17285788.



Linked-in.jpg