Our Staff


Our Doctors


Dr. David E. Hrncir

Owner and Practicing Physician

​Board Certifications:

  • Allergy & Immunology (Children and Adults)
  • Pediatrics
  • ​Aerospace Medicine

David E. Hrncir, MD, brings more than 30 years of experience in allergy and immunology, pediatrics, and aerospace medicine to San Antonio Asthma & Allergy, serving the men, women, and families in San Antonio, Texas, and throughout Bexar County. 

Dr. Hrncir is an owner and practicing physician at San Antonio Asthma & Allergy. He began his professional pursuits while in the United States Air Force Academy in Colorado Springs, Colorado. Then, he went on to obtain his medical doctorate from the University of Texas Southwestern Medical School in Dallas. 

Before entering private practice, Dr. Hrncir served as a chief flight surgeon in the United States Air Force. During his 26-year career, he received additional medical education at the School of Hygiene and Public Health, Johns Hopkins University in Baltimore, Maryland; David Grant Medical Center, Travis Air Force Base in Fairfield, California; The School of Aerospace Medicine at Brooks Air Force Base in San Antonio, Texas; and Wilford Hall Medical Center at Lackland Air Force Base, also in San Antonio, Texas.

As a member of the U.S. Air Force, Dr. Hrncir also held positions as the chief of pediatrics, chief of allergy and immunology, and chief of aeromedical services. Dr. Hrncir welcomes anyone seeking comprehensive care for asthma and allergies to San Antonio Asthma & Allergy.



Dr. John H. Freiler

Practicing Physician

Bio coming soon!

Our Staff


Claudia H. Glass FNP, MPH

Family Nurse Practitioner

Claudia Glass is a Family Nurse Practitioner who is pleased to work in the field of allergy, asthma and immunology providing care for patients of all ages. She is an experienced clinician in this specialty as well as vaccine safety, research, family practice and obesity care. As a Registered Nurse her areas of patient care included cardiac care, labor and delivery, pre/post op surgery, emergency, home health and renal failure.

Ms. Glass earned a Bachelor of Science degree in Nursing at The University of Louisiana at Lafayette and Master of Public Health with FNP specialty from Tulane School of Public Health and Tropical Medicine.  She has taught all levels of healthcare providers at Wilford Hall Ambulatory Surgical Center, the University of Texas Health Science Center San Antonio and Tulane University.

Ms. Glass is nationally certified through the American Nurses Credentialing Center.  She maintains professional affiliations with multiple professional organizations.




Dana takes care of our banking and payroll needs. She is the only one of our staff that you may not have contact with but plays a vital role in keeping us in business so that we may concentrate on the needs of our patients.



LVN Head Nurse

JoAnn has been part of our staff as Clinic Nurse for the past 2 years.  She has over 9 years of nursing experience. She came to us from Wilford Hall Allergy Immunology Clinic at Lackland AFB . With Allergy as her main focus she is dedicated to providing excellent nursing care to our patients by assisting our providers and amazing staff with all our patients medical needs. JoAnn is always available to our patients to answer any questions you may have regarding your office visit or medications.  



Medical Office Manager

Elaine Garcia recently joined San Antonio Asthma and Allergy Clinic, but she is not new to the insurance industry. Ms. Garcia has been in the medical billing industry for approximately 20 years. Ms. Garcia has billed for Asthma, Allergy, Immunology, General Surgery, Psychiatry and a Sterile Compounding Pharmacy. Ms. Garcia is always available to help with any insurance questions or issues they may have. Here at San Antonio Asthma and Allergy Clinic we believe that our patients come first.



Administrative Assistant

Jessica has been with San Antonio Asthma and Allergy Clinic for 6 years. Her top priority in our office is patient care and making sure everyone leaves here feeling like family. She loves working with terrific doctors and amazing staff who take their time with, listen to, and truly care about their patients. 

San Antonio Asthma & Allergy
2833 Babcock Rd., Suite #304
San Antonio, TX 78229
Phone: 210-614-7594
Office Hours

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