Pollen and Eye Allergies—What Should You Know?

Quick pop quiz: what’s the leading cause of allergies in Canada?

Pet dander? Dust? Medications? Or pollen/grass?

If the guess is the first three—close, but not quite! The correct answer is pollen and grass. More than 40% of Canadians with allergies report being allergic to pollen, the most common culprit for allergies. [1]

What is pollen and why does it give trouble to our eyes? More importantly, is there a way to enjoy the long-awaited spring and warmer seasons without itching and burning eyes? Let’s find out.

What is Pollen?

Scientifically speaking, pollen is defined as “male gametophyte of gymnosperms and angiosperms”. But let’s keep it simple. Pollen is fine, tiny grains or seeds released by plants like grass and trees. [2]

They come in various shapes like round, oval, disc/triangular-shaped, etc. Pollen grains can also vary in sizes, for instance, forget-me-not pollen is 6µm in diameter while birch tree pollen is 100µm in diameter and even certain plants producing as large as 200µm. [3]

For comparison, red blood cell in human body is ~5µm in diameter [4] and the average human hair diameter ranges between 70μm and 100μm. [5]

These fine to coarse ‘powders’ of pollen grains serve a key purpose: reproduction. Plants rely on various methods to spread pollen; certain types use the wind. As pollen is tiny, it can be easily airborne, travelling distance from where they originate. [6]

Yet, this is where the problem may start for allergy sufferers. Airborne pollen travels and reaches our eyes and noses, triggering potential ocular allergies.

When Does Pollen Start to Spread?

Throughout the year, pollen levels shift, depending on the type of plant and the season:

Tree pollen

Snow covers most of Canada in winter. As winter fades, tree pollen is the first to arrive, often catching us off guard with allergies. From February to May, depending on the regions in Canada, trees begin releasing pollen, with levels peaking in early spring. [7]

Birch, oak, maple, cedar, and alder are common examples of trees that release pollen and may play a role in itchy eyes. [7]

Grass pollen

In late spring and summer (May to August), tree pollen levels decline, yet grass pollen takes over as the dominant allergen. [8] Found in parks, lawns, and fields, grass pollen is abundant everywhere.

But not all types of grass are responsible for allergy symptoms. The varieties may vary depending on the region; some common culprits are Ryegrass, Bluegrass, and Bermuda grass. [9]

Weed pollen

Transitioning to fall, grass pollen level falls. Those experiencing hay fever may start to feel some relief. But weed pollen starts to peak, making eye allergy symptoms persist. [10]

Which weeds cause allergies? Ragweed is the dominant cause of fall allergies [10] and other weeds like nettle, mugwort, and pigweed are also observed in rural and urban areas, triggering itchy eyes and sneezing. [11]

True or False About Seasonal Pollen Allergies

Question № 1: Pollen allergies only happen in the spring?

False: While spring is a peak season, grass pollen dominates in summer, and ragweed pollen may also make symptoms persist in fall.

Question № 2: Allergies are not serious?

False: For many, allergies may be inconvenient. On the other hand, for others, allergic reactions may have negative impacts. Seasonal allergies may reduce quality sleep or lead to poor performance at work. [12,13]

How Does Pollen Cause Allergies?

Pollen grains contain proteins that may trigger an immune response. Continued exposure to high levels of pollen proteins leave us sensitized to such allergens. Our immune system misidentifies the pollen proteins as harmful.

In response, a cascade of events takes place in our body to “fight off” the mistakenly perceived threat. As a result, one may experience itching, burning, and watery eyes. [14]

HYLO-DUAL® mini & HYLO-DUAL®—allergy + dry eye relief

While we can’t control the pollen levels in the air, limiting exposure can help reduce allergy symptoms:

• Keep indoor spaces clean—regularly vacuum to remove pollen that settles indoors

• Shower after being outside—washing off pollen from hair, skin, and clothes may prevent irritation

Even with the best precautions, pollen can still make its way into the eyes, especially when spending time outdoors. That's where HYLO-DUAL® mini and HYLO-DUAL® come in. They offer a powerful, yet gentle combo of proven allergy + dry eye relief:

• Ectoine immediately relieves allergy symptoms like itching and burning

• High molecular weight Sodium Hyaluronate provides long-lasting dry eye relief

• Sterile, preservative-free drops that can be used while wearing contact lenses

Find HYLO-DUAL® mini and HYLO-DUAL® Canada-wide at pharmacies, behind the counter, and at selected optometry and ophthalmology clinics.

Should you have any concerns about your eye health, please consult with your eye health professional for medical assistance.

CandorVision™ – Your eyes are everything!

References:

1. Brule S, McDiarmid C, McDonald H. Health Fact Sheets Chronic Conditions, 2017. [Internet]. Government of Canada, Statistics Canada; 2018 [cited 2025 Mar 11]. Available from: https://www150.statcan.gc.ca/n1/pub/82-625-x/2018001/article/54983-eng.htm 

2. Borg M, Twell D. Life after meiosis: patterning the angiosperm male gametophyte. Biochem Soc Trans. 2010 Apr;38(2):577-82. doi: 10.1042/BST0380577. PMID: 20298224. 

3. What is Pollen? (Background Sheet) [Internet].  The University of Western Australia; 2011 [cited 2025 March 11]. Available from: https://www.uwa.edu.au/study/-/media/Faculties/Science/Docs/What-is-pollen.pdf 

4. Diez-Silva M, Dao M, Han J, Lim CT, Suresh S. Shape and Biomechanical Characteristics of Human Red Blood Cells in Health and Disease. MRS Bull. 2010 May;35(5):382-388. doi: 10.1557/mrs2010.571. PMID: 21151848; PMCID: PMC2998922. 

5. Park JH, Ho YH, Manonukul K. Hair diameter measurement methods: micrometer caliper versus phototrichogram. Arch Aesthet Plast Surg [Internet]. 2023 Apr 30 [cited 2025 Mar 11];29(2):97-101. Available from: https://doi.org/10.14730/aaps.2022.00423 

6. Fattorini R, Glover BJ. Molecular Mechanisms of Pollination Biology. Annu Rev Plant Biol. 2020 Apr 29;71:487-515. doi: 10.1146/annurev-arplant-081519-040003. Epub 2020 Mar 11. PMID: 32160004. 

7. Gouvernement du Québec [Internet]. Seasonal rhinitis (hay fever); [cited 2025 Mar 11]. Available from: https://www.quebec.ca/en/health/health-issues/a-z/seasonal-rhinitis-hay-fever 

8. Schäppi GF, Taylor PE, Pain MC, Cameron PA, Dent AW, Staff IA, Suphioglu C. Concentrations of major grass group 5 allergens in pollen grains and atmospheric particles: implications for hay fever and allergic asthma sufferers sensitized to grass pollen allergens. Clin Exp Allergy. 1999 May;29(5):633-41. doi: 10.1046/j.1365-2222.1999.00567.x. PMID: 10231323. 

9. AAAAI | American Academy of Allergy, Asthma & Immunology [Internet]. Mowing Down Your Grass Allergies; [cited 2025 Mar 11]. Available from: https://www.aaaai.org/tools-for-the-public/conditions-library/allergies/mowing-down-your-grass-allergies 

10. Asthma & Allergy Foundation of America [Internet]. Ragweed Pollen Allergy; [cited 2025 Mar 11]. Available from: https://aafa.org/allergies/types-of-allergies/pollen-allergy/ragweed-pollen/?gad_source=1&gclid=Cj0KCQjwjY64BhCaARIsAIfc7YZrKjVMvDTDYdq3g2nhxowVN0BQAngKwJpa46ACmk-o4Uq6vLUaZMIaAv1_EALw_wc 

11. ACAAI [Internet]. Seasonal Allergies | Causes, Symptoms & Treatment | ACAAI Public Website; [cited 2025 Mar 11]. Available from: https://acaai.org/allergies/allergic-conditions/seasonal-allergies/. 

12. Xi Y, Deng YQ, Chen SM, Kong YG, Xu Y, Li F, Jiao WE, Lu G, Tao ZZ. Allergy-related outcomes and sleep-related disorders in adults: a cross-sectional study based on NHANES 2005-2006. Allergy Asthma Clin Immunol. 2022 Mar 22;18(1):27. doi: 10.1186/s13223-022-00669-z. PMID: 35317862; PMCID: PMC8941730. 

13. Burton WN, Conti DJ, Chen CY, Schultz AB, Edington DW. The impact of allergies and allergy treatment on worker productivity. J Occup Environ Med. 2001 Jan;43(1):64-71. doi: 10.1097/00043764-200101000-00013. PMID: 11201771. 

14. Guryanova SV, Finkina EI, Melnikova DN, Bogdanov IV, Bohle B, Ovchinnikova TV. How Do Pollen Allergens Sensitize? Front Mol Biosci. 2022 Jun 16;9:900533. doi: 10.3389/fmolb.2022.900533. PMID: 35782860; PMCID: PMC9245541.