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Allergic Reaction (cont.)

What Is the Treatment for an Allergic Reaction?

Generally, antihistamine medications are the treatment of choice after the allergen is removed.

Very severe reactions may require other therapy, such as oxygen for breathing difficulties or intravenous fluids and/or epinephrine to boost blood pressure in anaphylactic shock. Patients with very severe reactions usually require hospitalization.

What Types of Medications Treat an Allergic Reaction?

There are many types of anti-allergy medications. The choice of medication and how it is given depends on the severity of the reaction.

For relief of long-term allergies such as hay fever or reactions to dust mites or animal dander, the following medications may be recommended or prescribed:

  • Long-acting antihistamines, such as cetirizine (Zyrtec), fexofenadine (Allegra), and loratadine (Claritin), can relieve symptoms without causing sleepiness. These medications are available over the counter. They are meant to be taken for months at a time, even indefinitely. Most can be taken once a day and last for 24 hours.
  • Prescription montelukast sodium (Singulair) is a type of antihistamine that can help relieve symptoms of allergic rhinitis.
  • Nasal corticosteroid sprays are widely prescribed for nasal symptoms not relieved by antihistamines. These medications work very well and are safe, without the side effects of taking steroids by mouth or injection. These sprays take a few days to take effect and must be used every day. Examples are fluticasone (Flonase), mometasone (Nasonex), and triamcinolone (Nasacort). Fluticasone and Nasacort sprays are now available over the counter.

For severe reactions, the following medications are usually given right away to rapidly reverse symptoms:

  • Epinephrine (EpiPen, Auvi-Q)
    • This drug is given only in very severe reactions (anaphylaxis).
    • It is injected and acts as a bronchodilator (dilates the breathing tubes).
    • It also constricts the blood vessels, increasing blood pressure.
    • For a less severe reaction involving the respiratory tract, an inhaled medication similar to epinephrine may be used, as in asthma.
  • Antihistamines, such as diphenhydramine (Benadryl)
    • This drug is given in an IV or in a muscle to rapidly reverse the actions of histamine.
    • Oral diphenhydramine is usually enough for a less severe reaction.
  • Corticosteroids
    • Corticosteroids are usually given via IV at first for rapid reversal of the effects of the mediators.
    • These drugs reduce swelling and many other symptoms of allergic reactions.
    • It will probably be necessary to take an oral corticosteroid for several days after this.
    • Oral corticosteroids (such as prednisone or methylprednisolone) are often given for less severe reactions.
    • A corticosteroid cream or ointment may be used for skin reactions.
    • Corticosteroid nasal sprays reduce the discomfort of a "stuffy" nose.
    • These drugs should not be confused with the steroids taken illegally by athletes to build muscle and strength.

Other medications may be given as needed.

  • In some people, cromolyn sodium (NasalCrom) nasal spray prevents allergic rhinitis, or inflammation of the nose that occurs as an allergic reaction.
  • Decongestants can restore sinus drainage, relieving symptoms such as nasal congestion, swelling, runny nose, and sinus pain (pain or pressure in the face, especially around the eyes). They are available in oral forms and as nasal sprays. They should be used for only a few days, as they may have side effects such as high blood pressure, rapid heartbeat, and nervousness.
Last Reviewed 9/11/2017

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