WHAT IS IT?
VOL: 100, ISSUE: 23, PAGE NO: 31
WHAT IS IT?
- Hayfever is seasonal allergic rhinitis.
- It is caused by the deposition of allergens (often pollen) on the nasal mucous membranes, resulting in a hypersensitivity reaction.
- Hayfever allergy can be hereditary and is linked to other atopic diseases such as asthma and eczema.
- Many patients maintain the allergy throughout life, while in some it may become milder. Sometimes it goes away completely.
- The main cause of hayfever in the UK is grass pollen, particularly perennial rye (Lolium perenne) and timothy grass (Phleum pratense). Symptoms peak during June and July.
- Symptoms in spring are commonly due to tree pollens.
- Late summer and autumn symptoms may be due to weed pollens and mould spores.
- Rapeseed may also provoke symptoms of rhinitis, although usually through irritant rather than allergic mechanisms.
- Due to high pollen counts, hayfever is most common during the spring and summer months.
- Between 15 per cent and 20 per cent of people in the UK have hayfever.
- Increasing numbers of people are reporting an allergy that makes them sneeze or feel nasally congested.
- People of all ages and both sexes have allergies that cause problems such as hayfever but more teenagers have allergies than any other age group.
- Nasal congestion.
- Possible loss of smell.
- Eyes itch.
- Frequent sneezing.
- Shortness of breath or wheezing.
- Dry coughing.
- Feeling of pressure in the sinuses.
- Examination of nasal passages and throat, and assessment of symptoms are normally sufficient.
- Tests for immunoglobulin levels (IgE) in the blood or skin-prick tests can be used.
- Sporadic - symptoms occur less than four days per week or for less than four weeks.
- Constant - symptoms occur more than four days per week and for more than four weeks.
- Mild - patients experience normal sleep, normal daily activities such as sport and leisure activities, normal work and school, and symptoms are not troublesome.
- Moderate - patients experience abnormal sleep, impairment of daily activities such as sport and leisure activities, problems caused at work or school, and troublesome symptoms.
Patients should be advised to avoid pollen by:
- Keeping all windows closed;
- Using sunglasses/protective eyewear to shield eyes from pollen particles;
- Staying away from high-pollen areas near trees and plants during the late afternoon and evening;
- Staying clean to keep pollen off clothing and hair;
- Checking the daily news for the pollen count.
- Oral antihistamines.
- Intraocular antihistamines.
- Intraocular sodium cromoglicate.
- Nasal antihistamines/steroids.
- Oral decongestants such as pseudoephedrine.
- Allergic immunotherapy can also be used. This involves introducing the allergens in small amounts into the body but is not normally recommended as it is a high-risk procedure.
TAKING A HISTORY
- Symptoms: past and present; frequency and severity; and provoking factors.
- Impact on lifestyle: absence from work or school; leisure time; sleep.
- Nature of occupation and hobbies.
- Treatment: past and present; compliance; efficacy; side-effects.
- Allergens in the home.
- Asthma, eczema, drug or food allergy: past and present.
- Family history of allergic disease.