What causes Allergic Rhinitis?

Causes

There are many substances in the environment which when inhaled cause allergic rhinitis. They include;

1.     House dust mites, which are found in mattresses, pillows, beds, and carpets. It is not the dust mites that cause rhinitis, but rather a chemical in their excrement. Dust mites are present all year round.

2.     Pollen from trees, grass, and weeds.

3.     Animal fur, hair, and their urine and saliva. Household pets, such as dogs and cats, are common culprits, but some people are affected by horses, rabbits, and rodents, such as guinea pigs and hamsters.

4.     Cockroaches

5.     Allergens in the work environment, such as wood dust, flour dust, or latex.

Aggravating factors

Some people have a genetic predisposition to allergic rhinitis, but it is the exposure to environmental factors that increases the risk of getting the condition and its subsequent severity. The environmental factors can be indoor or outdoor, and occupational.

The indoor factors include tobacco smoke, nitrogen dioxide from gas fired ovens, and formaldehyde in building materials. The home environment (like carpets) enhanced the survival of house dust mites. Outdoor factors include exhaust fumes from motor vehicles, particularly diesel, carbon monoxide, nitric oxide, and ozone.

Occupational pollutants include compounds like isocyanates and hexachloroplanates.

Associated conditions

There is a strong association between allergic rhinitis and asthma. About three quarters of patients with asthma also have allergic rhinitis. Allergic rhinitis frequently worsens asthma.

Sinusitis, which is an infection of the cavities inside the forehead and cheek bone (sinuses), is a common complication of allergic rhinitis. The normally air – filled with mucous instead, and if it is not drained away, infection from bacteria and viruses can ensue.

The allergen which affects the nose can also affect the sinuses. The usual symptoms are pain in the forehead, face or teeth, blocked or running nose, greenish or yellowish nasal discharge, coughing, and even fever.

Infections of the middle (orititis media) occur because the ear is connected to the nose by the Eustachian tubes, which can get infected. This condition is more common in children who have earache and even fever.