Airborne allergens are tiny particles in the air that can trigger allergic reactions in sensitive individuals. Common sources include pollen from trees, grasses, and weeds, as well as mold spores, dust mites, and pet dander. When inhaled, these allergens can cause symptoms like sneezing, runny nose, and itchy eyes. These allergens are often more prevalent during certain seasons, such as spring for pollen and fall for mold spores. People with allergies may benefit from monitoring local allergen levels and taking preventive measures, such as using air purifiers or staying indoors during high pollen counts.