Know all about Allergic Rhinitis

Allergic rhinitis is an allergic reaction that occurs in response to tiny particles such as pollen, mold, pet dander, insects (dust mites), etc. It is commonly known as hay fever. Allergic rhinitis is different from infectious rhinitis (the common cold).

Allergic rhinitis develops when a person breathes in allergens through the nose or mouth. In response to the allergen (a substance that causes an allergic reaction), the body releases a natural chemical called histamine. Allergic rhinitis may be more profound in certain seasons, such as spring, summer, and fall when there is evident growth of outdoor molds and pollen in the air from certain trees and plants. Symptoms of allergic rhinitis usually subside as winter sets in. 

Types of allergic rhinitis

Allergic rhinitis is broadly classified into 2 types, namely:

1. Seasonal (hay fever): This type is caused by allergies—as a result of pollen or mold spores in the air. These are especially prevalent during the spring, late summer, and fall when the flowering plants release pollen (fine powder) in the air. This is the most common form of allergic rhinitis.
   
   
2. Perennial: As the name suggests, the symptoms due to this type of allergic rhinitis remain throughout the year, irrespective of the season. It is mostly caused by pet hair or dander (dead skin cells, saliva, or urine), dust mites, or even molds.
   
   

What causes allergic rhinitis?

Typical allergens such as pollen from certain trees and weeds, mold, pet (cat and dog) dander, and particular insects (namely, dust mites) are the root cause of allergic rhinitis in a person. Other than these allergens, seasons also play a role in aggravating the symptoms of allergic rhinitis. In particular, the spring, summer, and fall seasons are not good for this condition, as during these months, the pollen release and growth of outdoor molds are more pronounced. 

Most allergens are harmless to the majority of people. If you suffer from allergic rhinitis (hay fever), your immune system recognizes these allergens as foreign substances. In order to protect your body from these intruders, the body starts releasing natural chemicals into your blood. These chemicals, called histamines, affect the mucous membranes of the nose, eyes, and throat region and cause itchiness and inflammation in order to eject the allergen from the body.

Rhinitis symptoms

Allergic rhinitis shows certain characteristic symptoms, which may vary from person to person in terms of severity. Following are some of the symptoms of allergic rhinitis:

• Nasal congestion, sneezing, runny nose
• Headache, sinus pain, and dark circles under the eyes
• Increased mucous secretion in nose and throat
• Itchy eyes, nose, and throat
• General fatigue and feelings of discomfort
• Coughing, wheezing, and difficulty breathing
• Sore throat due to mucous secretion in the throat
  
  

Allergic rhinitis diagnosis

To diagnose allergic rhinitis, your healthcare provider may ask you to undergo a skin test for a particular allergen. An allergic skin test is performed to determine what is causing the allergy. In this test, small amounts of the allergen are applied to your skin. If you are allergic to a particular allergen, your skin will feel tiny pricks that are generally not painful. The skin reaction to this allergen is observed and noted. You may also be asked to undergo an allergy panel test, which is a blood test to identify antibodies in your blood against allergens.

Rhinitis treatment

Once the causative allergen is known, it is easy to chart a course of treatment that is effective in alleviating the symptoms of allergic rhinitis. There are several medicines available these days to treat allergic rhinitis. Some of them are briefly described below:

• Antihistamines: These are a class of medications that help reduce symptoms such as itchiness, sneezing, and a runny nose caused by allergens. Generally available as OTC (over-the-counter) medicines in the form of pills and nasal sprays, these are very effective in controlling the above symptoms.
• Nasal steroid spray: These are effective in reducing nasal congestion and other reactions to inhaled allergens. It acts on the nasal tissues by reducing inflammation. These sprays are highly effective in treating chronic allergic rhinitis. However, they start showing their action at least 2 weeks after use.
• Decongestants: These are helpful in temporarily relieving a stuffy nose caused by an allergy. Decongestants come as nasal sprays, pills, and nose drops. Nasal sprays and nose drops should not be used for more than 3 days, as they can lead to dependency. They might lead to raised blood pressure at times; hence, it is important to consult a healthcare professional before beginning to use them.

• Immunotherapy: This therapy works by allowing your body to adapt to allergens. A series of injections (allergy shots) is given by your healthcare provider, who will gradually increase the amount of allergen with each shot. Over the course of a period, your body will become immune to the allergen and stop releasing histamines. This treatment can also be done in the form of a pill that can be placed under your tongue.
  
  

Allergy Panel Test

An allergy is a hypersensitivity disorder of the body’s immune system that triggers a series of undesirable reactions in response to a foreign substance known as an allergen. When such an event occurs, the body produces immunoglobulin E (IgE) antibodies. The levels of IgE antibodies in your blood go up more than normal when you suffer from an allergy. These IgE antibodies identify allergens as "threats" to the body and fight against them. Allergy blood tests are of two kinds, i.e., total IgE test and specific IgE test.

1. Total IgE test- This test is used to measure the total amount of IgE antibodies in your blood.
2. Specific IgE test- This is a separate test done for each allergy-causing allergen and measures the amount of IgE antibodies your body makes, in response to a single allergen.
   
   

For both of the above tests, a sample of blood is drawn from a vein in the arm using a fine needle. The sample is collected in a sterile test tube or vial and sent to the laboratory for further investigation. The results may be interpreted as follows:

• A high total IgE test result indicates that you have an allergy. However, it does not give information about what you are allergic to or how serious it is.
• A high specific IgE test result indicates that you are allergic to the particular allergen that was tested. However, the amount of IgE measured does not predict the seriousness of your allergy.

Although allergic rhinitis is not completely curable, its symptoms can improve with time. Since it is non-contagious, allergic rhinitis is different from infectious rhinitis or the common cold. Some ways of preventing allergic rhinitis include avoiding frequent touching of the face and rubbing of the eyes or nose, using filters in your vacuum cleaner and air conditioner to avoid spreading allergens in the air, maintaining personal hygiene by washing your hands often, etc. One must be extra careful if a family member is suffering from allergies, as these can be inherited. In the case of allergic rhinitis, it can certainly be said that "Prevention is better than cure!"