How geographic location affects your seasonal allergies.
Medically reviewed by Dr. Sarah Jenkins, MD, FACAAI
Verified ReviewerBoard Certified Allergist & Immunologist · Clinical Allergy, Asthma & Immunology
Stanford University School of Medicine
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Pollen counts and seasons vary drastically by geographic region. The "allergy capitals" often feature dense populations of allergenic trees (like oak, cedar, and elm) combined with weather patterns that trap pollen close to the ground.
| Region Type | Dominant Triggers |
|---|---|
| Northeast US | Tree pollen in spring, Ragweed in late summer |
| Southwest US | Mountain Cedar (winter), desert weeds |
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View sourceAmerican College of Allergy, Asthma & Immunology (ACAAI) "Allergy Facts and Figures" — ACAAI Clinical Resources.
View sourceWorld Allergy Organization (WAO) "White Book on Allergy — 2025 Update" — World Allergy Organization.
View sourceNational Institute of Allergy and Infectious Diseases (NIAID) "Clinical Guidelines for the Diagnosis and Management of Food Allergy" — National Institutes of Health.
View sourceMuraro A, et al. "EAACI food allergy and anaphylaxis guidelines: Diagnosis and management of food allergy" — Allergy — European Journal of Allergy and Clinical Immunology.
This content reflects clinical guidelines current as of the last review date shown above. Always consult a qualified healthcare provider for personalized medical advice.