An allergen is something that triggers an allergy. When a person with allergic rhinitis breathes in an allergen such as pollen or dust, the body releases chemicals, including histamine. This causes allergy symptoms such as itching, swelling, and mucus production.
Hay fever can be triggered by either seasonal or year-round (perennial) allergens. Many people have allergy symptoms all year long, but their symptoms get worse during certain times of the year.
Seasonal hay fever triggers include:
- Tree pollen, common in the spring
- Grass pollen, common in the late spring and summer
- Weed pollen, common in the fall
Spores from fungi and molds, which can be worse during warm-weather months
Year-round hay fever triggers include:
- Dust mites or cockroaches
- Dander (dried skin flakes and saliva) from pets such as cats, dogs or birds
- Spores from indoor and outdoor fungi and molds
Some disorders may be associated with allergies.
- These include eczema and asthma.
Your genes and environmental may make you more prone to allergies.
- If both your parents have allergies, you are likely to have allergies. The chance is greater if your mother has allergies.
Signs and symptoms of hay fever usually develop immediately after you're exposed to specific allergy-causing substances (allergens) and can include:
- Runny nose and nasal congestion
- Watery or itchy eyes
- Itchy nose, roof of mouth or throat
- Sinus pressure and facial pain
- Swollen, blue-colored skin under the eyes
- Decreased sense of smell or taste
Although hay fever can begin at any age, you're most likely to develop it during childhood or early adulthood. It's common for the severity of hay fever reactions to change over the years. For most people, symptoms tend to diminish slowly, often over decades.
After a medical history, your physician will perform a physical exam. Often, the nasal mucosa is pale or violaceous because of the engorged veins. Nasal polyps may be seen.
Allergy testing may reveal the specific substances that trigger your symptoms. Skin testing is the most common method of allergy testing. This may include prick, patch, or other tests.
Tests and diagnosis
Skin prick test : During skin testing, small amounts of purified allergen extracts are pricked into the skin of your arm or upper back and you're observed for signs of an allergic reaction.
- Allergy blood test : A blood test can measure your immune system's response to a specific allergen by measuring the amount of allergy-causing antibodies in your bloodstream, known as immunoglobulin E (IgE) antibodies.
Treatment of Allergic Rhinitis
- Nasal corticosteroids. These nasal sprays help prevent and treat the inflammation caused by hay fever. Examples include fluticasone, mometasone and beclomethasone.
- Oral corticosteroids. Corticosteroid medications in pill form, such as prednisone, are sometimes used to relieve severe allergy symptoms are prescribed for short term due to side effects.
- Antihistamines. These oral medications and nasal sprays can help with itching, sneezing and runny nose, but have less effect on congestion. Benadryl and clemastine. Over-the-counter examples include loratadine (Claritin, Alavert) and cetirizine (Zyrtec).
- Decongestants. Over-the-counter oral decongestants include Sudafed, Actifed and Drixoral. Nasal sprays include phenylephrine (Neo-Synephrine) and oxymetazoline (Afrin).
- Cromolyn sodium. This medication (NasalCrom) is available as an over-the-counter nasal spray that must be used several times a day. It helps relieve hay fever symptoms by preventing the release of histamine.
- Leukotriene modifiers. Montelukast (Singulair) is a prescription tablet taken to block the action of leukotrienes — immune system chemicals that cause allergy symptoms such as excess mucus production.
- Nasal atropine. Available in a prescription nasal spray, ipratropium bromide (Atrovent) helps relieve a severe runny nose by preventing the glands in your nose from producing excess fluid.
Other treatments for hay fever include:
- Immunotherapy. If medications don't relieve your hay fever symptoms, immunotherapy or desensitization therapy is done.
- Nasal lavage. To help with irritating nasal symptoms, rinse your nose with salt water.