Seasonal allergies are often viewed as a childhood condition, but adults can also develop new allergies, especially in their 20s, 30s, and 40s. According to Dr. Tolly Epstein, an adjunct assistant professor at the University of Cincinnati’s College of Medicine, it’s common for people to develop new allergies later in life.
Symptoms may not be immediately apparent, with sneezing, itchy eyes, or nasal congestion being the most common indicators. However, these symptoms can also manifest as fatigue, headaches, or sinus pressure, which may be mistaken for cold symptoms. Seasonal allergies occur when an individual’s immune system reacts to environmental elements like pollen or mold spores that circulate in the air during specific times of year.
The immune system triggers a chain reaction upon exposure, releasing chemicals like histamine, which can lead to sneezing, runny noses, and congestion. Experts are unsure why new allergies or symptoms may develop without prior presence, but several factors contribute to this phenomenon. Climate change is one cause, as it accelerates allergy season, making people more susceptible to developing symptoms.
Where a person lives and for how long also plays a role in determining their susceptibility to seasonal allergies. For some individuals, relocating to a new area can alleviate symptoms by removing exposure to former allergens, while others may encounter new issues due to the introduction of unfamiliar triggers.
Source: https://www.uc.edu/news/articles/2025/03/adults-can-develop-seasonal-allergies.html