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    What Are Antihistamines and Decongestants?

    Antihistamines and decongestants won't cure your allergies. But they’ll give you much-needed relief for a runny or congested nose.

    Antihistamines target histamine, which your body makes during an allergic reaction.

    You can take them as pills, nasal spray, or eye drops. The pills target itching, sneezing, and runny nose. The nasal sprays work on congestion, an itchy or runny nose, and postnasal drip. Some common ones are:

    • Cetirizine (Zyrtec)
    • Chlorpheniramine (Chlor-Trimeton)
    • Clemastine (Tavist)
    • Desloratadine (Clarinex)
    • Diphenhydramine (Benadryl)
    • Fexofenadine (Allegra)
    • Loratadine (Claritin)

    Antihistamines can ease your symptoms, but they work best when you take them before you feel a reaction. They can build up in your blood to protect against allergens and block the release of histamines. Ask your doctor if you should start taking allergy medicine a couple of weeks before you usually have symptoms.

    Decongestants cut down on the fluid in the lining of your nose. That relieves swollen nasal passages and congestion.

    Why Do You Have Allergies? Allergies can be irritating, but they’re nothing to sneeze at! What are the common triggers, and what actually happens inside your body? 67

    Your immune system is designed

    to defend your body

    against dangerous invaders

    like bacteria and viruses.

    But sometimes it overreacts

    to harmless things like grass,

    dander, or pollen.

    When this happens, your body

    is having an allergic reaction.

    Things that cause

    allergic reactions are called

    allergens and vary from person

    to person, like bee stings,

    medications, shellfish,

    or peanuts.

    Once your immune system

    recognizes the allergen,

    it triggers your white blood

    cells to release antibodies.

    These cells release chemicals

    called histamines that produce

    the symptoms

    of an allergic reaction,

    like sneezing, wheezing,

    itchy eyes, or hives.

    Allergies are very common

    and usually pretty minor.

    But sometimes a reaction can be

    sudden, severe, and potentially


    This is known as anaphylaxis.

    For minor reactions,

    try over-the-counter treatment

    like antihistamines,

    anti-inflammatory steroid

    creams, eye drops, or ice

    packs to ease your symptoms.

    For more serious cases,

    your doctor may prescribe

    allergy injections, epinephrine,

    or corticosteroids.

    Allergies may be irritating,

    but they're nothing to sneeze


    Pixeldust Studios
    Mayo Clinic: "Bee Sting."
    National Institute of Allergy and Infectious Diseases: "Food Allergy."
    University of Maryland Medical Center: "Allergic Reactions."
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    You can take these by mouth in pills or liquids, like pseudoephedrine. 

    Some pills with decongestants are:

    • Chlorpheniramine/phenylephrine (Actifed)
    • Loratadine/pseudoephedrine (Claritin-D)
    • Phenylephrine (Sudafed PE)
    • Pseudoephedrine (Sudafed)

    Some medications combine antihistamines and decongestants. Their names usually end with “-D.”

    Decongestant Nasal Sprays

    Decongestant nasal sprays are another possibility. They shrink the swelling inside your nose to make you less stuffy. And they do it fast. Some sprays are:

    • Oxymetazoline (Afrin)
    • Phenylephrine hydrochloride (Neo-Synephrine)
    • Xylometazoline (Otrivin)

    There's a catch, though. If you use them more than a few days in a row, your swelling and stuffiness may get worse. This is called a "rebound reaction." You get temporary relief, but your symptoms come back worse than before.

    If you use nasal decongestant sprays, limit it to 3 days max.

    Another Option: Steroid Nasal Sprays

    Nasal steroids are a type of nose spray and are often the first drugs recommended for allergies. They're a powerful way to fight stuffiness because they get to the root of the problem.

    They lessen the whole allergic inflammatory process. Plus they target all your allergy symptoms, not just congestion.

    Some options are:

    • Beclomethasone 
    • Fluticasone (Flonase)
    • Mometasone (Nasonex)
    • Triamcinolone (Nasacort)

    If you use one, be patient. You don't get the full effect for several days or even a week. But if you use it daily, it can be very effective. 

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