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allergies

living with allergies: testing, treatments and clearing the air

marie taylor discovered she had allergies when she was trapped in a car with a cat.

by robin roberts

published jan 11, 2024

last updated jan 12, 2024

7 minute read

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7 minute read

join the conversation

living with allergies: testing, treatments and clearing the air

animal allergens also fall into the inhaled category and, contrary to the belief that it’s the hair that spurs an attack, it’s generally the tiny particles of pet dander, saliva and urine that hover in the room and settle on furniture and carpets, even when the pet is not around. getty images

marie taylor discovered she had allergies when she was trapped in a car with a cat. the okanagan, b.c., resident was in her late teens and had hitched a ride with friends to a party. her upbeat mood quickly took a downturn, however, when her eyes began to water, her nose got stuffed up, and she started to sneeze. “what is happening?,” she wondered.

“it could be the cat,” said her friend.

cat?

that’s when taylor noticed the cat carrier at the feet of her friend in the front seat. occupant: one big, fluffy, dander-filled feline. but she was still bewildered. “i had never had an allergy before,” says taylor.

even more bewildering, she had grown up around dogs and cats since she was a baby and had never had an issue. “but after that happened with the cat in the car, anytime i was around any cat it would happen again.”

anatomy of an allergy

an allergy is a multifactorial condition caused by genetics and your environment, according to asthma canada, and includes food, drug, animal, insect, hay fever, dust and mould allergies.

when your immune system encounters an allergen, it responds by producing an antibody called immunoglobulin e, which releases histamine into your bloodstream to do battle with the offending invader. that action is what causes the sneezing, sniffling, stuffy nose, itchy hives, watery eyes and blocked ears.

“at least 25 per cent of canadians are afflicted [with allergic rhinitis, also called hay fever], but that number is probably higher,” says dr. anne ellis, professor in the department of medicine, as well as clinician scientist who studies allergic rhinitis, at queen’s university. “lots of people don’t see their doctor about their symptoms. so somewhere between 20 and 40 per cent is the real number.”

according to asthma canada, if both your parents have allergies, you have a 75 per cent chance of getting one too. ellis says having a mom with allergies is the biggest risk factor.

before puberty, boys tend to be more affected, she says; after puberty, girls are more commonly affected, with hormones being the likely trigger. some kids will outgrow them, but they may reappear later, and quieten down again as they age and their immune responses become less active.

penicillin and seasonal allergies tend to lessen with age, while allergies to foods like peanuts, tree nuts and shellfish tend to plague people for life. some estimates say 50 to 80 per cent of kids will outgrow milk or egg allergies by age 10.

while most allergies develop in childhood, experts say onset of allergies in adults, like taylor’s, is not unusual. why they happen, they haven’t a clue. some believe it’s the puberty theory, others say pregnancy, chronic illness or organ transplants — anything that messes with your immune system, essentially — can bring them on. which isn’t much help to people like marie taylor, who has never been pregnant, had a chronic illness or an organ transplant (although her mother had a reaction to sulfur). but, in addition to her cat allergy, she soon developed reactions to horses and dogs.

and while she doesn’t respond the same to dust, mould or pollen, they are among the most common allergens. asthma canada breaks down allergens into inhaled — seasonal pollen from trees, grass and ragweed, as well as mould spores, that float in the air — and perennial allergens, such as dust mites that live in our furniture, beds, carpets and drapes and feast on our dead skin.

ick.

“the biggest thing when it comes to allergic reactions, which is sometimes easier said than done, is removing or avoiding triggers, such as smoke, pet dander, scented candles, fragrances,” says jeffrey beach, president and ceo of asthma canada. “but some people have severe allergies to chemicals that we encounter all the time. some have serious allergic reactions to dust and dust mites, which are basically everywhere, and that can be difficult for people to manage.”

testing for allergies

ellis, who is also president of the canadian society of allergy and clinical immunology (csaci), says that although they are not the same thing, asthma and allergies are related in that they both affect breathing by blocking the free passage of air between the nose and lungs.

“at least 80 per cent of asthmatics will also have allergic rhinitis, or will have allergic triggers for their asthma,” she says.

according to asthma canada, because many of the underlying processes in the immune system are similar, having allergies increases your risk of having asthma. and, if you have asthma, you’re at a higher risk of having allergies.

concerned she could be susceptible to other allergens, taylor saw an allergist who did a skin test. using a tiny needle, the doctor deposited a small amount of allergen under her skin to see if she had a reaction. the test proved positive for dogs, cats, horses (the worst) and dust (least).

doctors will also sometimes recommend a blood test that looks for the level of the immunoglobulin e antibody that causes the allergic response.

dos and don’ts of allergy treatment

taylor’s treatment is non-pharmacological: she just steers clear of four-legged, fur-bearing hairballs. other therapy options depend on the type, cause and severity of the allergy and whether or not you can completely avoid the triggers.

over-the-counter relief includes eye drops, lotions and creams, saline sprays and washes, decongestants, inhalers, nasal sprays, syrups and antihistamines. if these don’t do the trick, your doctor may prescribe something stronger, such as corticosteroids that reduce inflammation; leukotriene receptor antagonists (ltras), which block the chemicals causing the allergic reaction; immunotherapy, which in effect desensitizes your body to the foreign invader; or an epinephrine injector if your allergies are severe enough to cause anaphylactic shock.

taylor’s doctor recommended an antihistamine but the cure was worse than the condition. “it made my heart race. i felt like i was going to have a heart attack,” she says.

ellis cautions against the use of some antihistamines for that very reason. “i only support second-generation antihistamines that have gone through proper, randomized controlled trials to show they’re safe and effective,” she says. “older antihistamines, like diphenhydramine [the medicinal ingredient in benadryl], were grandfathered by the fda. so nobody had to study them, nobody had to look at the safety aspects. we [now] know that those older antihistamines are quite unsafe. not only do they cause sedation, they can cause arrhythmia [racing or irregular heartbeat]. and, if you overdose, it can cause death.”

she says that, despite these dangers, particularly for children, these older antihistamines are still on canadian shelves. in 2016 and again in 2019, csaci issued a position statement stating their concerns, and they continue to sound the alarm, but to date, health canada has not restricted their use.

she says the non-sedating second- and third-generation antihistamines, such as claritin and reactine, not only have fewer side effects, they work better. studies have shown vitamin d can also be beneficial for easing allergies.

clearing the air

ellis says research into better allergy therapies are ongoing. one study completed last spring revealed that taking an antihistamine much sooner before exposure to an allergen produces a much better outcome.

“allergists have told people for years to take antihistamines before you’ll be exposed to your allergen,” she says. “we did a study with fexofenadine, which is under the brand allegra in canada, that proved that two days of pre-treatment with fexofenadine significantly reduces symptoms compared to [taking it just before encountering the trigger].”

if your allergies are mild enough to not require meds, however, asthma canada recommends avoiding allergens and keeping your space as clean as possible. if you can’t part with your pet, create pet-free zones in your home and bathe pets often to keep the dander down. avoid carpets, drapes, feather pillows and padded headboards, all magnets for mites; trade horizontal blinds for pull-down blinds, which collect less dust; use anti-allergy mattress and pillow covers; vacuum often and use one that has a hepa filter; use a damp mop or rag to dust; eliminate or minimize house plants; consider a dehumidifier; and bypass mould-prone areas like basements.

beach advises keeping on top of your in-home filtration systems, which are designed to trap allergens. “we encourage people who have issues with respiratory allergies to ensure they are using proper filtration devices. if the air is not filtered properly through your heating and cooling system, it’s basically just circulating the allergens around.”

as for the air out there, particularly with severe summer wildfires across the country, beach says asthma canada, in partnership with lung health organizations, advocates for clean air and clean energy initiatives. “[we encourage] the federal government to look at air quality issues from an outdoor and indoor perspective and ensure there are incentives and greater availability of resources such as air purifiers for people who meet those requirements. we have also advocated for the phase-out of coal-fired electricity generation. there is such an intersection between air quality and the health and well-being of people with asthma and other respiratory health conditions.”

while clearing the air is helpful, there’s the hygiene hypothesis that claims an overly clean environment weakens a child’s maturing immune system. “we had that message out quite clearly, and then covid hit,” says ellis. “so i do wonder if we’re going to see another mini wave of the allergy epidemic in children who were born and raised during covid times.”

meantime, beach encourages people with respiratory allergies to check out all the information, resources and webinars on asthma canada’s website, including how to self-advocate when navigating the healthcare system with allergies.

robin roberts

living with allergies: testing, treatments and clearing the air