Making the Diagnosis
The important thing to remember about in hay fever is exactly when the rhinitis appears and disappears. Knowing these dates will give a doctor or an allergist vital clues as to what's provoking the symptoms, and makes diagnosis easier.
By getting the details of where you live and work and when you suffer most, a doctor or an allergist can make a very short list of possible causes. Allergists use small, standardized doses of all the most common allergens to narrow down the diagnosis. They test for allergy by gently scraping the skin with each of these until they get a small rash. Most of these tests are nearly painless.
If none of the skin tests produce results, it's probably some other kind of rhinitis. These other conditions can be confused with hay fever:
- Vasomotor rhinitis: the nasal mucous membrane swells up with increased blood flow, causing runny nose and congestion, but typically no itching. There's no specific cause - patients aren't allergic to anything - although smoke, dry air, temperature change (such as coming in from the cold), and odours can trigger symptoms.
- Chronic rhinitis: may be prolonged symptoms of a common cold or another disease, for example syphilis or tuberculosis.
- Rhinitis medicamentosa: caused by overusing nasal spray decongestants, which actually increase congestion if used for more than about 10 days. Cocaine users are also vulnerable to this form of rhinitis.