Many people have allergies that last all year round that are triggered by specific substances, like cat hair, snake venom, insect bites, peanuts, wheat, soy, shellfish, and even common foods like eggs and milk. These persistent reactions go under the heading of perennial allergies.
As well, there are many millions of people in the United States (estimates put the numbers at around 19 million adults and 5 million children) who show reactions that are triggered by changes brought about by shifts in the seasons. Most frequently, this is noticed beginning in March and lasting through to the early summer months. These seasonal allergies are caused mainly by the start of tree pollination, which begins earliest in the year, and later is followed by grass pollination.
Typically, the spring/early summer allergies are triggered by airborne pollen coming from trees, flowers and grasses that release their spores as the temperatures rise. The specific allergies are different for different people, generally depending on which type of pollen or irritant your immune system reacts to.
In the case of seasonal allergies, you may only experience the start of symptoms at the same time and for the same weeks or months each year. This doesn’t mean that your reactions could not be triggered by a different trigger, in which case you might find more marked changes from year to year.
What is changing?
According to an article published in the New York Times (April 29th, 2022), several studies have shown that the seasons which affect most people are starting earlier and lasting longer. Although no direct causes for this are known, it’s felt that generally warmer temperatures attributable to climate change, and rising levels of CO2 in the atmosphere are pushing the boundaries of the seasons outwards.
Some other weather patterns not directly related to global warming or CO2 levels are also known. In the winter months just past (October 2021 to March 2022), average temperatures across the northern US states were slightly elevated, and in the southern states even more so, according to data from the National Centers for Environmental Information. Milder winter temperatures may cause trees and plants to pollinate early, releasing their spores into more windy weather patterns that will carry them further. If this is followed by a rainy spring season, it could cause symptoms to last right through the summer months.
Some of the following weather patterns also can influence how widely allergies may be felt:
- Levels of tree and grass pollens rise during cool nights and warm days
- All pollen levels usually peak in the early hours of the day
- Although rain will wash the pollen out of the air, pollen counts can rise quickly after rainfall
- Airborne triggers require wind to disperse, so they are grounded on windless days. Conversely, if a day is windy and warm, pollen levels will rise.
What are the recommended treatments for seasonal allergies?
A bit like for colds and flu, there’s no single treatment that will cure it or even substantially reduce the symptoms. Most approaches try to reduce the greatest discomforts, which depend primarily on your own specific reactions to the trigger. The main strategies for symptoms like running nose, sneezing and the like, doctors can suggest these drugs:
- Steroid nasal sprays containing fluticasone propionate (for example, Flonase), budesonide (Rhinocort) or triamcinolone (Kenacort)
- Oral antihistamines to help relieve sneezing, running nose, as well as itching and watery eyes. Examples include fexofenadine (Allegra Allergy), cetirizine and loratadine
- Oral decongestants to provide temporary relief from nasal stuffiness. This includes pseudoephedrine. Some allergy medications combine a decongestant with an antihistamine. Examples include Dexamol, Clarinase and Sinutab.
FAQ
What seasons cause the most allergies?
Every person is different and your own pattern of allergies, in terms of what can trigger the reaction, and when, is very much a matter of your own body chemistry. However, the transition from cooler months produces a strong growth in pollen levels, and this is the most predominant trigger for allergic reactions. Therefore, most people who suffer from seasonal allergies will be affected in the spring and early summer months.
What symptoms can seasonal allergies cause?
Seasonal allergy symptoms vary depending on which allergen triggers your own immune response. It will also affect the severity of the symptoms. While it’s not possible to list every possible reaction that you may personally encounter, the following list covers the most frequent and common signs:
- Nasal congestion and stuffiness
- Runny nose and sneezing
- Persistent coughing
- Itchy throat
- Red, swollen eyes
- A build-up of sinus pressure
- Sore throat.
What are the different types of seasonal allergies?
The seasonal patterns depend on the types of pollen that are being released by flowering plants. Over the seasons, these are:
- Spring – grass and tree pollen, weed pollen
- Summer – fungus spores, grass pollen, and mold
- Fall – weed pollen, dust and mold
How do you know if I have allergies or a cold?
Although the symptoms may be very similar, there are some distinctions that you and your medical advisors should be able to pick up on.
- A cold is frequently accompanied by a fever. Typically, symptoms of seasonal allergies mimic those of a cold (runny nose, sore throat, coughing etc.) but less often produce a fever
- A cold should normally clear up over five to seven days, with the symptoms generally diminishing after the first 2-3 days. Allergies can last right through the season, for weeks and even months
- If you have an allergy triggered by a seasonal change, it will usually show up each year at roughly the same time. Colds and flu are less predictable.
