Allergic rhinitis is inflammation of the inside of the nose caused by an allergen, such as pollen, dust, mould or certain animal danders.

Allergic rhinitis often causes cold-like symptoms, such as sneezing, itchiness and a blocked or runny nose. These symptoms usually start soon after being exposed to an allergen.

Some people only get allergic rhinitis for a few months at a time because they are sensitive to seasonal allergens, such as tree or grass pollen. Other people get allergic rhinitis all year round.

Causes

Allergic rhinitis is caused by the immune system reacting to an allergen as if it were harmful. The immune system is the body’s natural defense against infection and illness.

If your immune system is oversensitive, it will react by attacking allergens in the same way it attacks viruses and infections.

Known allergens include pollen (this type of allergic rhinitis is known as hay fever), house dust mites and certain animals.

Symptoms

Most people with allergic rhinitis have mild symptoms that can be easily and effectively treated. However, for some, symptoms can be severe and persistent, causing sleep problems and interfering with everyday life.