Leon S. Greos, MD

Dr. Leon Greos joined Colorado Allergy and Asthma Centers in 1993. He is certified by the American Board of Allergy and Immunology. Dr. Greos emphasizes prevention of allergy symptoms through identification of triggers, patient education and rational use of preventive medicine.

Dr. Greos received his bachelor’s degree from Amherst College and doctor of medicine from the University of Southern California School of Medicine. Following his internship and residency at the University of Washington, Dr. Greos completed fellowships in pediatrics and allergy and clinical immunology at National Jewish Center for Immunology and Respiratory Medicine. Dr. Greos entered private practice in Sacramento, California before returning to Colorado to join our group.

The most stimulating aspect of allergy and asthma care, according to Dr. Greos, is attempting to discover the particular pattern of each patient’s condition and effective care.

Schedule an Appointment with Leon S. Greos, MD

IMPORTANT PLEASE READ: If you are a new patient or require testing, please stay off antihistamines for 7 days prior to your appointment. Also, if you are an established patient but have not been seen for over 3 years, you will need to schedule a New Patient Appointment.


Wisdom From Leon S. Greos, MD

Climate Change and Your Allergies

08.08.2011 | Leon Greos, MD

Colorado-A Growing Community Many patients have commented that their allergies seem to have gotten worse in recent years.  Some of this change may be related to the population growth that we have experienced over the past 25 years along the Front Range in Colorado.  The growth brings more traffic and congestion, construction dust, and landscaping... Read more »

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