Key points

• Seasonal allergy symptoms usually start in early spring and are highly prevalent.
• An allergic inflammatory state may activate immune cells in the brain.
• Seasonal allergies can affect mood, mental sharpness, and decision-making.

Spring is a beautiful season when all nature is rebirthing. After the dark and cold days of winter when dominant colors are white and shades of grey, we love to see our nature starting to bloom in a rainbow of colors. However, blooming nature also sends out a great deal of different pollens that cause seasonal allergies. They develop when our body's immune system overacts to something in the environment. It may be surprising to find out that seasonal allergies are highly prevalent; they affect 10-40% of the general population, this author included.

The most common symptoms are sneezing (when pollens irritate the mucus membrane of the nose); running nose; itchy nose, mouth, and throat; and itchy and watery or red eyes. However, seasonal allergies can also cause headaches, nausea, cough, and sore throat, as well as fatigue, high blood pressure, peripheral inflammation, disordered sleep, and impaired cognition. (An allergic inflammatory state may activate immune cells in the brain.) Obviously, if you have difficulty sleeping and are fatigued (which may also be a result of disordered sleep), you will have difficulty functioning in family and school and/or work situations. However, some research suggests that allergies, in addition to increased fatigue, can also cause increased sleepiness (Tamm, S. at al. 2018).

Research studies indicate that allergies can cause a variety of cognitive problems. The Marshal and Colon study (1993) indicated that people who suffered from seasonal allergies (without taking medications) exhibited a decline in verbal learning, slower decision-making, and slower psychomotor speed compared to non-sufferers. Allergies can also cause difficulties in working memory, or the ability to perform mental operations on immediate memory (Marshal, P.S. at al. 2000).

Some healthcare professionals compare allergy symptoms to “brain fog” (feelings of lacking mental clarity, being mentally sluggish and/or fuzzy), which is also frequently seen in long-term Covid-19. Studies on children suffering from seasonal allergies indicated problems in spatial working memory, longer reaction time in cognitive tests, and longer reaction time for simple movement (Papapostolou, G. et al. 2021). However, allergy sufferers did show a decline in sustained attention, which is a great plus, I would say.

In addition to cognitive problems, seasonal allergies can also affect our mood and sense of well-being. The Marshal and Colon study (1993) indicated that seasonal allergy sufferers had lower positive affect during the allergy season. Other studies indicated an increased risk for depression, but no changes in anxiety as compared to controls (Trikojat, K. et al 2017; Hurwitz, E.L. and Morgenstern, H. 1999). Studies of rodents suggest that peripheral allergic inflammation affects the brain and may be a factor in developing neurodegenerative diseases (Sarlus, H. et al. 2012). Other studies indicated that, unlike humans, rodents exposed to pollen had anxiety-like behavior and reduced social interactions (Tonelli, L.H. et al 2009).

The most common treatment for seasonal allergies are allergy shots (done in a doctor’s office) and sublingual solutions (not covered by most health insurance). There are also many over-the-counter allergy medications and supplements that may reduce your symptoms. However, it is important to talk to your healthcare provider before taking them, especially if you have health problems and/or take prescription medication.

If your seasonal allergies affect your mood, sleep, and cognition and interfere with your daily life, school, and/or work performance, you may try counseling. Taking a pill may reduce your allergy symptoms, but may not help improve your overall functioning during allergy seasons. “Pills do not talk” and will not help you effectively deal with problems you are experiencing in daily functioning, but therapy may help.

About the Author

Barbara Koltuska-Haskin, Ph.D., is a neuropsychologist in private practice in Albuquerque, New Mexico with over 30 years of clinical experience, and the author of How My Brain Works: A Guide to Understanding It Better and Keeping It Healthy. Her book has won 2 International Book Awards and 5 National Book Awards.