Dr Cathy Stephenson: Hay Fever
Dr Cathy Stephenson has some advice on managing hay fever
Hay fever (also known as "allergic rhinitis") affects up to 30% of adults, and 40% of children in New Zealand&so several 100,000 New Zealanders are suffering the symptoms during spring and summer months, and this season seems to have been especially bad. It can have a huge impact on quality of life - affecting sleep, school or work performance, and ability to engage in social activities. It can also be a trigger for asthma in susceptible individuals.
There are 2 types of allergic rhinitis:
1. Seasonal rhinitis - which only occurs during certain seasons, usually spring and early summer; it is classically triggered by outdoor allergens (eg pollens);
2. Perennial rhinitis - year-round symptoms; triggered by indoor allergens (including house dust mite, pets, moulds).
Sneezing; nasal congestion; watery eyes and nose; itchy throat, eyes and nose; sinus pressure and facial pain or headaches; reduced sense of smell or taste.
Children may present with tiredness, eye-rubbing, speech problems, snoring, dark circles under their eyes, sniffing and blinking.
What causes it?
Allergens in the air enter the nose, throat and eyes, triggering an "immune-mediated reaction" in the cells of the upper airway passages. These cells release a substance called histamine, which causes all of the above symptoms.
What are the commonest allergens?
Pollens - from trees in spring, and grass in summer
House dust mite
Pet hair, fur or feathers
Some foods (especially milk, eggs, peanuts).
Who is affected?
Anyone can be affected at any age. It is not uncommon for people to grow into it, or indeed out of it, at any stage.
It is closely linked with asthma and eczema - a spectrum of conditions known as "atopy". Hay fever will occur in up to 80% of people who also have asthma, and a family history of "atopy" makes the diagnosis of hay fever much more likely.
Is it serious?
It is not a life-threatening condition in itself - although it can and does make life very unpleasant for many sufferers. However, it is important to get the symptoms well-controlled as there is a risk of exacerbating asthma, and triggering a potentially serious attack.
In most situations, a Dr will be able to diagnose you with hay fever based on your symptoms alone. Whether your symptoms are "seasonal" or "perennial" will help them work out what allergens you may be sensitive to. However, sometimes a referral for further testing may be considered useful. The most available test for this in New Zealand is skin prick testing - it may help determine possible sensitivity to a specific allergen, but it is not always reliable and may not be appropriate, or helpful, for many sufferers. Occasionally, a referral to either an allergy specialist or an ENT (ear, nose and throat) specialist may be indicated if the diagnosis is in doubt.
1. Managing the environment:
Avoid the allergen as far as possible (if you have been able to identify it).
Pollen counts are highest in the morning, and on sunny, windy days with low humidity. Different plants flower at different times of year, so try and avoid being outside for long periods if the particular plant you are allergic to is likely to be in flower. The met service website now has a daily pollen forecast, to help you predict the pollen count. There is also an annual pollen calendar for different plant species in New Zealand on the Allergy NZ website (see below for details).
Stay indoors if pollen counts are high or it is especially windy.
Splash you eyes with water regularly, and try gently rubbing some Vaseline inside your nose - this may reduce the effects the allergen may have.
Wear sunglasses when outside.
Use air-con when in the car (on re-cycle mode).
Avoid mowing lawns or raking leaves yourself.
Have lawns mowed regularly as this will avoid the grass flowering.
Select low-allergenic plants (a local garden centre should be able to give you advice).
Use a clothes-dryer to finish off bedding - this will reduce the amount of pollen that may have settled while on the washing line.
For other allergens:
Keep pets outside.
Use a dehumidifier indoors.
Remove carpets, or vacuum regularly (preferably not yourself!) as carpets are often a source of dust mite.
Cover all bedding, and remove any soft toys from the bedroom.
Antihistamines - these can be used either orally, or as a nasal spray. They can be very effective for people with occasional, mild symptoms. They can be purchased over the counter - but are much cheaper when prescribed by a Dr. They work quickly so can be used on an "as required" basis. They are safe in children over 2 years old (in the correct dosage) - but sedating types such as Phenergan are no longer recommended and should be avoided in children of all ages. Antihistamine eye drops (such as Livostin or Lomide) are really effective at treating any eye symptoms.
Steroids - steroid nasal sprays are currently the most effective treatment, and will help with all the major symptoms of hay fever. They start to work within 12 hrs, but may take 2 weeks to reach their maximum effect. They are best used regularly (unlike antihistamines) and can be commenced before the pollen season starts - to try and prevent the symptoms flaring up. They are used once or twice a day, depending on the preparation. Occasionally, symptoms will be so severe, or so resistant to other medication, that oral steroids will be required. This will usually be a 5-7 day course of prednisone tablets, and can be prescribed by your Dr. There is no longer any indication for an intramuscular steroid injection to be used for hayfever - it is risky, and has no greater benefit than when used orally. Unfortunately this is still a common practice.
3. Immune therapy:
This treatment involves regular injections of an allergen under the skin, and eventually results in de-sensitisation. It can be an extremely effective treatment for people with very severe symptoms. However, it is not widely available in New Zealand, and is both costly and time-consuming. If successful, the benefits can last for many years.
Visit www.allergy.org.nz (information, advice and the "pollen calendar")
www.metservice.com (daily pollen forecasts)
Discuss with your Dr about treatment options, or referral to a local allergy specialist.