Springtime and seasonal allergies

Seasonal allergies have a hereditary component: if one of our parents has them, our chance of having them increases. A family history of seasonal allergies is still one of the most important tools for diagnosis and prognosis [6]. In addition, children with atopic dermatitis (eczema) are also more likely to develop other allergies during their lifetime, including asthma, allergic rhinitis and food allergies. The more severe and persistent the eczema, the higher the risk. [7].

The best way to prevent seasonal allergies is to avoid exposure to pollens, as much as possible, especially in the morning and at the end of the day, when their concentration in the air is higher.

Here are a few tips from the Institut national de santé publique du Québec (INSPQ) for reducing your exposure to allergens [8]:

• avoid opening your home and car windows;
• shower and change your clothes after spending time outdoors;
• wear sunglasses and a mask to reduce exposing your face to airborne allergens;
• avoid drying your clothes outside to prevent pollen from building up on the fabric;
• reduce exposure to respiratory irritants like tobacco smoke;
• avoid outdoor physical activities in areas with high pollen counts.

When avoiding allergens is no longer enough, there are a number of options for relieving seasonal allergy symptoms. However, some precautions should be taken, especially for pregnant women.

Rinsing your sinuses with salt water (saline) can help clear them. You can use a traditional nasal bulb or more sophisticated devices, available in pharmacies. You can also buy ready-to-use saline solutions or make your own at home with simple easy-to-find recipes online [9].

Antihistamines are often the first treatment to try for seasonal allergies. Available over the counter in pharmacies, they are usually safe and effective. However, first-generation antihistamines such as chlorpheniramine (e.g., Chlor-Tripolon®), and diphenhydramine (e.g., Benadryl®) are relatively short-acting and can cause side effects like drowsiness and dry mouth and eyes. More recent antihistamines such as cetirizine (e.g., Reactine®), loratadine (e.g., Claritin®) and desloratadine (e.g., Aerius®) are long-acting and cause fewer side effects [10].

Nasal sprays containing a decongestant are also available without a prescription. These products, by inducing vasoconstriction of the blood vessels, help relieve congestion, but do not directly address the allergy. These products should not be used for more than 3 days, as they may cause rebound congestion.

Also available as a spray, these anti-inflammatory medications help reduce inflammation, which is the cause of allergic rhinitis symptoms. They are available following a consultation with a doctor or pharmacist.

The first step in desensitization is to identify the source of the allergy such as trees, shrubs, herbs and grasses, a skin test performed by an allergist will then be done. Desensitization involves repeated injections of small doses of an allergen.

This treatment should be followed over a period of several months to allow the body to gradually get used to the allergen. This is a solution for people with more severe symptoms such as allergic asthma, who have not responded to standard treatments.

People who are allergic to pollen molecules may also react to certain specific foods. This cross-reactive allergy occurs when food molecules too closely resemble pollen proteins. The immune system overreacts, triggering allergy symptoms such as itching, mild swelling, and sneezing. These symptoms are usually mild and localized but can sometimes be more severe. Aside from avoiding these foods, cooking them may be a good option, as heat denatures the molecules, which could reduce the allergic reaction [12].

Here are some common pollen-food associations [13]:

• Birch pollen: Apple, pear, peach, cherry, carrot, hazelnut
• Ragweed pollen: Banana, cantaloupe, watermelon, cucumber
• Mugwort pollen: Garlic, celery, carrot, anise, coriander

Sensitivity to seasonal allergens varies considerably in pregnant women. For some women, symptoms worsen, while for others, they don’t seem to change or may even improve. If this occurs, worsening of their rhinitis symptoms usually disappears after giving birth. However, an uncontrolled allergy during pregnancy can affect the mother’s sleep and overall well-being. Poorly controlled allergic asthma can also reduce the oxygen supply to the fetus, hindering its development and increasing the risk of prematurity. Also, it is important to discuss with a healthcare specialist to find out which medications are safe during this time [14].

Seasonal allergies are a widespread and increasingly concerning public health problem, compounded by climate change. With global warming, this problem could intensify, particularly for at-risk people like those with asthma. Although seasonal allergy symptoms are rarely severe, they can disrupt daily life. Fortunately, avoidance and prevention strategies, as well as medical treatments, can help better manage symptoms and improve the quality of life of those affected.