WILL THIS BE A BAD YEAR FOR HAY FEVER?
That all depends on the weather. Normally, rain dissipates pollen, but in dry conditions it blows straight into the air, where it can then easily get into the eyes and nose.
What we do know for sure is that pollen seasons are getting longer. A US study published in February found that the pollen season extended by 30 days between 1990 and 2018
So instead of starting in March and ending in September, it is now starting in late February, and continuing into October.
WHY ARE SYMPTOMS WORSE SOMETIMES?
Hay fever symptoms tend to be worst around 11am and 6pm, and this is because pollen is at nose level, says Dr Adrian Morris, a specialist based at the Surrey Allergy Clinic.
"Pollen starts off on the ground at the beginning of the day, so at 8am the pollen is all sitting on the grass," he says.
"As the day warms up, the grass also warms and the pollen particles are shed and rise up in the air.
"At about 11am, they're at nose level - around 5ft off the ground. During the course of the day, the pollen then goes very high up into the atmosphere and, as it cools down during the course of the day, the pollen grains come down to earth again and at about 6pm they tend to be back at nose level.
"That's why there are two times of the day when people tend to be particularly vulnerable."
Watch the weather forecast. Gentle rain can ease symptoms because it washes the pollen out of the air and on to the ground, out of harm's way.
But during a thunderstorm, the pollen grains can explode into smaller particles, which can penetrate deeper into the airways and so exacerbate symptoms.
Gentle rain followed by still, sunny weather creates the perfect condition for a pollen 'bomb' - a massive surge of pollen.
The rain feeds the production of pollen, the warm weather triggers its release and the lack of wind keeps it hanging in the air.
A hot, sunny day with little wind can also be a problem because pollen stays airborne for longer.
CAN ADULTS DEVELOP HAY FEVER?
A recent survey by Allergy UK found nearly half of people questioned said they had suffered hay fever for the first time in the past five years.
While it usually starts in childhood, adults can suddenly be affected, says Dr Kariyawasam: "Most commonly, those who are genetically prone to allergies start with eczema in infanthood, with hay fever then following in adolescence."
It takes time for the immune system to become sensitive to pollen, so most people aren't struck down with hay fever for the first time until they are between 18 and 25, explains Professor Adam Fox, a consultant in allergies at Evelina London Children's Hospital.
It's still possible to develop hay fever in your 30s or 40s but it would be unusual to be a first-time sufferer in your 60s or 70s because the immune response wanes with age.
IS IT HAY FEVER - OR DO I HAVE COVID?
There is some crossover with the symptoms of Covid and hay fever, says Dr Kariyawasam. "With both you can get flu-like symptoms - and as a result some people with hay fever feel they just want to go to bed, just as those with Covid may."
But while a high temperature is one of the defining symptoms of catching coronavirus, hay fever does not cause a fever, adds Dr Morris.
Whereas the immune response to a virus generates chemicals that cause a fever, a different part of the immune system is triggered with allergies and this does not include fever-generating chemicals.
It can take a few days for antihistamines to take effect, so start them around three days before you expect hay fever symptoms to begin Sultan Dajani, pharmacist
IS IT WORSE IN THE COUNTRY?
This is another myth, says Dr Morris. "Many people don't realise there is a higher proportion of hay fever sufferers in cities than in the countryside."
Increased air pollution may be to blame, especially particulates (microscopic particles) from diesel fumes, for triggering the condition and exacerbating hay fever in those who have it.
A study published last year in the Journal of Allergy and Clinical Immunology found that people who live in areas of higher pollution are more likely to have more severe nasal symptoms.
People who already have allergies are likely to have worse symptoms if they are in a polluted environment, says Professor Sir Malcolm Green, founder of the British Lung Foundation.
"There is also evidence that people who would not normally develop allergies are tipped over into becoming allergic because of mucosal irritation caused by pollutants," he adds.
WHEN SHOULD I START TAKING MEDICATION?
If you know you suffer from hay fever, take action in advance, says pharmacist Sultan Dajani.
"It can take a few days for antihistamines to take effect, so start them around three days before you expect symptoms to begin.
"In the meantime, you can use corticosteroid nasal sprays, such as mometasone furoate [brand name Nasonex] or fluticasone propionate [Flonase], available over the counter, to override some of the symptoms until the antihistamine start working properly."
These reduce local inflammation and are different from decongestants, which can help relieve stuffiness but need to be stopped after three days because they can cause "rebound rhinitis".
"If you keep taking them, you become tolerant, the medication doesn't work any more and you get the symptoms back but worse than before."
Creams containing an antihistamine can help reduce urticaria (skin rashes) caused by hay fever.
Eye drops containing sodium cromoglicate (such as Optrex) can help with red, itchy eyes by reducing the release of histamine and can be used up to four times a day.
WHY DO I GET DROWSY ON ANTIHISTAMINES?
Antihistamines attach to histamine receptors and block the chemical histamine, which is released as part of an allergic response and causes itchy eyes and sneezing.
Medicines such as chlorphenamine can cause drowsiness because they cross into the brain, where they affect sleep and wakefulness, says Sultan Dajani.
"Newer antihistamines such as cetirizine, loratadine and fexofenadine don't cross into the brain and so don't cause drowsiness - although, as a result, they may be slightly less effective."
SHOULD I PUT VASELINE AROUND MY NOSTRILS?
Sultan Dajani suggests ignoring the common advice to smear petroleum jelly around your nose to 'catch' the pollen grains before their enter your nose: "It is breathing in pollen that's the problem and this won't stop this. It will just make a sticky mess."
But there can be some benefit, says Dr Morris. "When someone has hay fever, the nose can be very itchy and irritated from constant sneezing. Rubbing on a layer of petroleum jelly can protect against this."
More useful is a face mask and wraparound sunglasses. "Ordinary [surgery-style] blue masks will act as a barrier and reduce the number of pollen grains entering your nose and mouth - although not completely as the pollen particles are very small," says Sultan Dajani.
WILL I GROW OUT OF HAY FEVER?
Yes you can - symptoms typically start to improve from the age of 40 onwards, says Dr Kariyawasam.
That's because symptoms begin when immune cells called B lymphocytes mistakenly identify the proteins on pollen as a threat and make antibodies in response.
These antibodies (known as IgE) bind to mast cells, triggering the release of histamine, which tries to rid the body of the threat, causing symptoms such as sneezing and watering eyes.
"However, as we get older we produce less IgE," says Dr Kariyawasam. "I always say 40 is a turning point for this, but for most people symptoms significantly improve after 60."
YOUR PET CAN GET HAY FEVER, TOO
"Dogs and cats can get hay fever when exposed to grass and tree pollen, just like their owners," says Daniella Dos Santos, senior vice president of the British Veterinary Association and a small-animal vet in Buckinghamshire.
"Their symptoms tend to be different: the main symptom is itchy skin. Dogs with hay fever are also prone to ear infections."
To help you and your pet, the animal charity Blue Cross suggests wiping your dog's fur, skin and paws with a damp cloth to remove pollen after a walk, washing bedding regularly and keeping your lawn well-mown - short grass releases less pollen.
HOW DIET MAY HELP WITH SYMPTOMS...
There is some preliminary research suggesting that probiotics (live, 'friendly' bacteria) may help alleviate hay fever symptoms.
Prof Adam Fox says: "The thinking is that the way that our immune system responds to the outside world is quite significantly influenced by the microbiome, the bacteria that colonise our gut.
"So if you have a 'healthy' microbiome, it skews your immune system to more appropriate responses and less allergic responses, whereas if you have an 'unhealthy' microbiome it can skew you the other way.
"But it's early days and there are no clinically relevant randomised trials to show probiotics may help."
However, some dietary strategies may help. Dietitian Carrie Ruxton says: "A way of helping to calm the immune response is by having more omega-3 fats as these are anti-inflammatory.
"Good sources are salmon, trout, mackerel and prawns.
"Studies suggest eating local honey every day during hay fever season may lessen symptoms."
© Daily Mail
