Our History

A History of Service & Success

Established in 1971 by Fannie Lou Leney, M.D. as a pediatric allergy facility, the Northwest Allergy Clinic was located in the United Founders Medical Building.  In 1977, John L. Davis, M.D. purchased the Clinic and moved it to the Baptist Medical Center campus.

In the early 1990’s, the Clinic relocated to the Deaconess North Medical Office in Okahoma City, where it remained until 2007 when Jason Sigmon, M.D. assumed the leadership role of the clinic from the retiring Dr. Davis.

in 2018, Dr. Simon moved to Steamboat Springs, CO with his family.

Yampa Valley Medical Center Ears, Nose and Throat Clinic represents a bold step forward to help alleviate the sneezing, suffering and sinus problems that adversely affect thousands of Coloradans.  We can help you take charge of the allergy and sinus problems that threaten to compromise your overall health and threaten the quality of your life.


1971 – Northwest Allergy Clinic established by Fannie Lou Leney, M.D.
1977 – Allergy Clinic purchased by John L. Davis, M.D.
1982 – Hundreds of Oklahomans have been treated for seasonal allergy disorders
1993 – Northwest Allergy Clinic celebrates 20 years
2007 – Dr. Davis retires; Jason Sigmon, M.D. takes ownership of Clinic
2008 – To better reflect its mission, Dr. Sigmon re-names the practice to Northwest Sinus & Allergy Clinic
2011 – Northwest Allergy Clinic moves to 3330 NW 56th Street, Suite 110 in Oklahoma City, OK  73112
2017 – Northwest Allergy Clinic moves to a more convenient location at 10960 North May Avenue in Oklahoma City, OK  73120

2018 – Dr. Sigmon moves to Steamboat Springs in Colorado.  His practice is named Yampa Valley Medical Center Ears, Nose and Throat Clinic.

Jason Sigmon, MD, FAAOA

My allergies are gone.  My sinus problems are gone.  Both thanks to Dr. Jason Sigmon.

Jennie Lovel