An update on hay fever treatments
Rhinitis refers to inflammation of the mucous membrane of the nose. It can be allergic or non-allergic in origin. Non-allergic causes include viral infections, changing hormone levels, triggers such as cold weather or spicy foods, and drugs (eg, angiotensin-converting enzyme inhibitors).
Allergic rhinitis involves the production of allergen specific IgE (after exposure to an allergen), which binds to mast cells. Subsequent exposure causes degranulation of these cells, resulting in the release of chemical mediators, such as histamine, and the production of leukotrienes and prostaglandins, leading to itching, runny nose, sneezing and nasal congestion. Infiltration of inflammatory cells follows, worsening nasal
Traditionally allergic rhinitis has been categorised as seasonal or perennial but, more recently, it has been classified as intermittent or persistent, and as mild or moderate/severe. Symptoms that occur occasionally, lasting less than four weeks or less than four days per week, are described as intermittent allergic rhinitis. Persistent allergic rhinitis describes symptoms for more than four weeks and more than four days per week. It is caused by allergens that are present all year round, such as house dust mite, feathers and animal dander.
Seasonal allergic rhinitis, commonly known as hay fever, can fall into either of these categories. It is caused by with allergens that only occur at certain times of the year, such as tree pollen (spring), grass pollen (end of spring, beginning of summer), weed pollen (early spring to end of autumn) and fungal spores (autumn). The timing of symptoms may indicate likely allergens but some people are sensitive to many types of pollen and suffer persistent symptoms. About 90 per cent of people with hay fever are allergic to grass pollen and about 25 per cent are allergic to birch pollen.
The average age of onset of symptoms is 10 years with incidence peaking between 13 and 19 years. It has been suggested that the increase in the incidence of hay fever (and other allergies) is due to a decrease in the number of childhood infections.
Download PDF (140K) for full article
Citation: Electronicjuice URI: 10909165
Recommended from Pharmaceutical Press
The Obesity Epidemic and its Management explains the causes, dangers and treatments of obesity.£38.00