Investigations and Diagnosis
History of the patient is important in identifying the allergen. Skin prick test is useful, but it is not a confirmative test. Allergen specific IgE antibody levels in the blood can be measured, but it is expensive.
- Allergen avoidance
- H1 antihistamines- commonest therapy (ex: Chlorphenamine, Hydroxyzine, Loratidine, Desloratadine, Cetirizine, Fexofenadine)
- Anti-inflammatory drugs
- Corticosteroids- most effective
What is Nonallergic Rhinitis?
Any nasal condition with the symptoms of allergic rhinitis but whose etiology is unknown is defined as the nonallergic rhinitis.
Several internal and external factors may cause nonallergic rhinitis.
External factors include,
- Viral infections (cold) which attack the lining of the nasal cavity and the throat
- Environmental factors like high temperature, humidity, exposure to noxious fumes
Internal factors include,
- Hormonal imbalance
- Hormonal replacement therapy or hormonal contraception
Common Cold (Nonallergic Rhinitis)
A variety of respiratory viruses such as rhinovirus, coronavirus, and adenovirus can cause this highly infectious illness. Among them, rhinovirus is the commonest causative agent. Since the rhinovirus has several serotypes, it is not possible to design a vaccine against the virus. The disease characteristics are limited to the upper respiratory tract because the virus grows well at 33’C which is the local temperature of the upper respiratory tract. The transmission is mainly through close personal contact (nasal mucus on hand) or respiratory droplets. Overcrowding and poor ventilation facilitate the spread of the infection.
Signs and Symptoms
- Slight pyrexia
- Profuse watery nasal discharge