Allergic rhinitis, commonly known as Hay fever or simply allergy, occurs when the immune system overreacts to certain particles in the air called allergens. Common allergens like dust, pollen and animal dander, and mold spores can trigger an episode of allergic rhinitis. It can also be triggered by some medicines and food.
The symptoms of allergic rhinitis may manifest within a few minutes to hours after the allergen comes in contact with the body. In some cases, the symptoms can last for days.
The symptoms which appear in minutes after contact include
- Sneezing fits
- Excessive nasal secretion
- Watery and itchy eyes
- Itchy ear nose and throat
The symptoms that take time to manifest include:
- Nasal congestion and obstruction
- Breathing through the mouth because of a blocked nose.
- Fatigue and irritability
- Discomfort or pain in the face
The first time a susceptible individual is exposed to a certain allergen, the body’s immune system recognizes and marks the allergen as a foreign matter. The body reacts by producing antibodies against the allergen.
When the body is exposed to the allergen again, the antibodies react to it, releasing Histamine that triggers a series of events leading to the symptoms of allergy.
To diagnose an allergy, the doctor takes an in-depth history of the condition. Knowing the symptoms, the time of the day when it happens, and other information regarding the symptoms helps the doctor to make an educated guess about the allergy.
Skin test: In this test, a small amount of allergen is exposed to the skin to see if it elicits an immune response. Other lab tests are available to look for allergens that might cause the allergies. These tests help pinpoint the exact allergen or allergens responsible for the allergic reaction.
Avoiding the allergens responsible for the allergy: Avoiding the allergen is the best way to prevent an allergic episode. The best way to do this is by making sure that the contact with the causative allergen is minimal.
Manage symptoms: Antihistamines are the first line of treatment for allergic rhinitis as Histamine is the endogenous chemical responsible for most of the symptoms. Nasal corticosteroids and other nasal decongestants can be used to reduce nasal congestion.
Immunotherapy: If the allergy affects the daily routine, suppressive immunotherapy might be recommended. This treatment starts with the introduction of minute quantities of the allergen into the blood stream followed by the gradual increase of the dose until the symptoms can be controlled. This treatment dampens the immune response to the allergen. Any future contact with the allergen doesn’t elicit an overreaction from the immune system.
Dr. A S Sanjay
MBBS,Cert course in Diabetology, Ex-Capt(AMC)