HAYFEVER - Full extract 

Hayfever is an allergic condition characterized by a runny nose, sneezing and itchiness of the eyes and throat. It is often a seasonal complaint that is worse in Spring, when there are plenty of pollens, ryegrasses and flowering plants. It is a common condition. About 20% of Australians get hayfever, and the incidence seems to be increasing. The word hayfever is a misnomer; it is rarely triggered by hay and there is certainly no fever associated with the condition. 

The mucous membrane layer of the nasal passages contains special allergy cells called mast cells; these have been primed by antibodies our bodies have produced from previous exposures to allergens like pollens and animal dander. The cells have special receptors on their surface to connect with allergens; once this occurs they release histamine granules and other substances to set off the sniffling, slobbering and sneezing. People with perennial rhinitis suffer similar symptoms all year round, but instead of having an allergic basis, this condition is often aggravated by temperature and humidity changes. 

The housedust mite is a tiny organism that lives in dust and feeds on flakes of dried skin and bits of lint. Quite a large number of people are allergic to the dust mite and it causes both hayfever and asthma in susceptible people. Keeping the environment as free of dust as possible is an important part of hayfever treatment, even if it means getting rid of dustcatchers like musty carpets and old pillows. It also helps to keep household pets away from bedroom areas and to minimize exposure to cigarette smoke. 

Asthma, eczema and hayfever are an allergy trio that tend to travel along together, either in the one person or in various members of the same family. Hayfever and sinusitis are often often confused. These two conditions are at either end of a spectrum. Whilst hayfever is caused by allergy, sinusitis is caused by infection and is characterized by nasal blockage, facial pain and a thick discharge from the nose. A fever may be present and the person may be quite ill. Frequently the distinction is not so clear and the person may have features of both; this may occur in a hayfever sufferer who happens to have an occasional episode of sinusitis. 

The treatment of hayfever has improved markedly in recent years, mainly due to the introduction of preventive nasal sprays and the non-sedating antihistamine tablets. The newer antihistamines are far less likely to cause sleepiness or interfere with concentration. However, care is required because some antihistamines can have an uncommon interaction with certain medications like the antibiotic, Erythromycin, and some anti-fungal tablets. 

There are several types of preventive nasal sprays for use in adults and children; they contain the same medications as preventive asthma sprays and are equally effective. Some people with hayfever make the mistake of relying upon over-the-counter decongestant sprays. This can be quite a problem because the sprays can sensitize the nose and lead to a severe rebound effect when they are stopped.

For people with persistent hayfever symptoms, desensitization injections can be a great help. It is especially helpful for allergies to grass pollens. The patient is usually referred to a specialist allergist who does various skin tests to identify the precise allergens that are responsible. Then follows a series of fortnightly injections for several months. The person is exposed to gradually increasing amounts of the allergen and the sensitivity is progressively reduced. The procedure is well-tolerated and usually very successful. 

Health Tips:
* There is no place for nasal decongestant sprays in the long-term treatment of hayfever.

* If you are taking antihistamines from the pharmacist, check with your doctor when any other medications are prescribed.

Dr. Andrew Pattison: Common Consultations
North East Valley Division General Practice, Melbourne, Australia.   Disclaimer
  - Last modified: August 18, 2001