Allergic rhinitis is a condition characterized by symptoms like running nose, nasal blockage and red, itchy, teary eyes. It is an allergic response triggered after exposure to allergens (pollen, dust, pet handling). Allergic rhinitis is commonly called “hay fever”, but neither hay nor fever is associated with it. The most common cause of allergic rhinitis are the pollens are shed by the grass at the time of “haying” hence the name. The symptoms of allergic rhinitis are quite debilitating, but avoidance of allergens and medication improves the condition.
Common symptoms are :
- Thin, watery nasal secretion
- Itching of eyes, mouth, face or any other area
- Nasal stuffiness
- Difficulty in smelling
- Ear blockage
- Generalized body pain, fatigue
- Puffiness under the eyes
- Red, teary eyes
Complications are :
- Poor quality of life, reduced activity.
- Aggravation of asthma, eczema, sinusitis, ear infections.
Some symptoms of the common cold (viral infection) and allergic rhinitis (allergic manifestation) may overlap, but there are some important differences. Allergic rhinitis is immediately precipitated upon exposure to allergen and relieved with removal of allergen whereas the common cold takes 2 to 3 days to manifest after viral exposure 3 to 7 days to recover. Fever occurs in common cold but absent in allergic rhinitis.
Sometimes the immune system wrongly identifies an airborne foreign substance (like pollen) as an antigen and starts producing antibodies against them. Subsequent exposure to the substance (allergen) leads to allergic manifestation (due to antigen-antibody reaction). Common allergens are :
- Pollens: Pollens causing hay fever varies from person to person. Sources are trees (pine, birch, alder), grass (most common allergen causing allergic rhinitis) and weeds (ragweeds). Usually dry windy weather increases the amount of pollens in the air but rainy, moist weather washes away pollen.
- Animal dander
- Chemical substances like detergents can aggravate symptoms of allergic rhinitis.
- Suffering from other type of allergy like eczema and asthma.
- Family history.
- Weather: inhabitant of dry weather.
- Constant exposure to chemicals and animals (saliva, fur).
The aim of treatment is :
- To avoid exposure to allergen – not always possible.
- Medical treatment to reduce the hypersensitivity and inflammation.
- Corticosteroids: prescribed orally or nasally. Nasal corticosteroids (fluticasone, triamcinolone, mometasone) are first line drugs whereas oral steroids (prednisolone) are reserved for severe cases. Usual side-effects of steroid preparations are almost nil with nasal route administration thus can be used for long term duration.
- Antihistaminics: prescribed orally (fexofenadine, cetirizine), as nasal spray (azalastine) or eye drop (olopatadine). Relieves nasal, eye symtoms effectively.
- Decongestant: prescribed orally, as nasal spray (phenylephrine). Oral tablets can cause raised blood pressure, headache and irritability as side-effects. Nasal sprays should not be used for more than 2 to 3 days as there is chance of increased (rebound) congestion.
- Nasal ipratropium, cromolyn sodium (nasal spray).
- Allergen immunotherapy (allergy shots): patients not adequately managed by drugs are treated with shots. Regular injections of doses of allergen are given (dose is gradually increased).
Most cases of allergic rhinitis are treated successfully with drugs alone few cases require shots. Children can outgrow allergic symptoms as sensitivity of the immune system towards allergens decreases with age.