Thread by @NightShiftMD

Your seasonal allergies are getting worse. A thread on why. 1/n

Seasonal allergies are getting worse in Canada and around the world. That means longer allergy seasons and more severe symptoms. 2/n

One reason is that climate change has led to warmer temperatures and longer growing seasons. These extend the time that pollen is in the air.3/n

Warmer temperatures throughout the year lead to an earlier start to allergy season. In addition, increased atmospheric carbon dioxide associated with climate change leads plants to produce more pollen as well as pollen that is more potent. 4/n

We used to have distinct allergy seasons brought on (for instance) by pollens produced by trees, grass and ragweed. Now, these distinct seasons tend to overlap, making it seem as if it’s all one lengthy period of symptomatic misery. 5/n

Allergies are affecting more people than ever…so much so that the World Health Organization has recognized seasonal allergies as a global health issue. 6/n
.pmc.ncbi.nlm.nih.gov/articles/PMC40…

Urban planning is another factor. City planners have long recommended planting pollen-producing trees rather than messier fruit-bearing trees…further contributing to higher pollen levels. 7/n

The symptoms of seasonal allergy haven’t changed although they may be more severe. They include nasal congestion and post nasal drip, sneezing
itchy eyes, nose and throat, fatigue, cough and wheezing.8/n

To minimize symptoms, stay indoors when symptoms are severe such as when it’s windy and rainy. Reduce your exposure to pollen by closing windows at home and in the car. If you must go outside on heavy pollen days, wear a hospital mask.9/n

Effective treatments include prescription and non-prescription antihistamines, nasal corticosteroids, and decongestants.10/n

Allergy shots are a form of immune therapy in which you are given injections of pollen extract beginning with a small dose and gradually increasing over six months and continuing for three to five years. The shots condition your immune system to make antibodies that block the production of other antibodies that trigger allergies. 11/n

Immune therapy can also be taken in tablet form that is placed under the tongue once each day beginning before the pollen season and continuing until the season is concluded. The cost is approx $1 per tablet, and is not uniformly covered by the provinces. 12/n

Omalizumab or Xolair has shown promise in treating seasonal asthma and can also be effective for seasonsl allergic rhinitis or hay fever. The downsides are that the medication is very expensive ($15-30k per year) and must be taken once per month continuously to reduce allergy symptoms. 13/n