JOSEPH DIAZ, M.D. | Medical Director - AllergySA - San Antonio Allergist - Asthma

JOSEPH DIAZ, MD | Medical Director

San Antonio-born, Dr. Diaz followed in his father’s footsteps, Jose A. Diaz, M.D., family practitioner, who had a successful medical practice on the south side of San Antonio for 30 years.

Dr. Diaz graduated from St. Mary’s University in San Antonio, with high honors and a B.S. in Biology. He received his medical degree from the University of Texas Medical Branch at Galveston, Texas. His internship and residency, as well as his fellowship in Allergy and Immunology, was completed at the University of South Florida College of Medicine. Since opening his private practice, Allergy, Asthma and Immunology Associates of South Texas in 1988, Dr. Diaz has served as clinical assistant professor in the Department of Internal Medicine at the University of Texas Health Science Center in San Antonio. He was appointed Co-Director of the Allergy/Clinic Immunology Fellowship training program and directed the program for several years.

In addition to his private practice, Dr. Diaz is the President and Medical Director of Allergy and Asthma Research Center, established in 1989. As Medical Director of the Research Center, Dr. Diaz says his patients benefit from access to new medicines and information not yet available to most physicians or patients. In Dr. Diaz’ free time, he enjoys physical fitness, competing in Iron Man competitions and spending time with family.

LUKENA KARKHANIS, M.D. | Board Certified - AllergySA - San Antonio Allergist - Asthma

LUKENA KARKHANIS, MD | Diplomate, American Board of Allergy and Immunology

Dr. Karkhanis joined Allergy SA in 2014. Dr. Karkhanis is board certified in Internal Medicine and Allergy and Immunology. Dr. Karkhanis received her medical degree with honors from Seth G.S. Medical College and K.E.M. Hospital in Mumbai, India. She was engaged in research activities at the University of Pittsburgh, after which she completed her internship and residency in Internal Medicine at St. Luke’s-Roosevelt Hospital Center and Columbia University in New York, New York and her fellowship in Allergy and Immunology from Washington University School of Medicine and Barnes-Jewish Hospital in St. Louis, Missouri.

She is an active participant in national allergy meetings, and has presented and published multiple reports. She is also an active member of the following organizations: American Academy of Allergy, Asthma, and Immunology, American College of Allergy, Asthma, and Immunology, Texas Medical Association, Texas Allergy, Asthma, and Immunology Society and San Antonio Allergy, Asthma, and Immunology Society. Dr. Karkhanis works with pediatric and adult patients to help treat allergies and asthma.

She also serves as a Sub-Investigator on several studies at the Allergy and Asthma Research Center, which keeps her abreast of the latest developments in the field. In her spare time, she enjoys art, literature, culinary experimentation and spending time with her family.

Raul Villarreal, MD

RAUL VILLARREAL, MD | Diplomate, American Board of Allergy and Immunology | Board-Certified, American Board of Internal Medicine

Dr. Raul Villarreal joins AllergySA as our newest physician serving both pediatric and adult patients at our South Side and Stone Oak Locations.

A native Texan, he completed his undergraduate studies at Rice University in Houston, Texas and earned his medical degree from the University of Texas Southwestern in Dallas, Texas. He completed his Internal Medicine Residency at McGaw Medical Center of Northwestern University in Chicago, IL and his Fellowship in Allergy and Immunology at the University of South Florida where he served as Chief Fellow during his final year.

Dr. Villarreal has been an active presenter at both regional and national allergy meetings and has been published in The Journal of Allergy and Clinical Immunology and Annals of Allergy, Asthma & Immunology. He has also been a sub-investigator in several food allergy, asthma, and eczema clinical research trials including studies on peanut oral immunotherapy and biological treatments for atopic conditions.

In his free time, Dr. Villarreal enjoys traveling abroad, exploring the local food scene, physical fitness, and spending time with family and friends.

Marie Celeste Loera, MSN, FNP-BC | Nurse Practitioner Board Certified - AllergySA - San Antonio Allergist - Asthma

MARIE CELESTE LOERA, FNP-BC | Nurse Practitioner, Board-Certified

Ms. Loera joined Allergy SA in January 2012. A native of San Antonio, she attended Health Careers High School and earned her BSN from the UT Health Science Center at San Antonio. During her postgraduate studies at UTHSC, she was inducted into the Sigma Theta Tau International Nursing Honor Society and completed the Family Nurse Practitioner Program with a Master of Science in Nursing degree in 2011. She is dedicated to the fundamentals of her practice and is committed to providing compassionate, patient-centric care, tailored to the individual.

She is a member of the American Nurses Association, Texas Nurses Association, National Association of Hispanic Nurses, American Association of Nurse Practitioners and the Texas and San Antonio Allergy, Asthma and Immunology Society. She provides supervision and instruction as a Clinical Preceptor for The University of Texas Health Science Center.

She is very passionate about community leadership programs and serves as an Anaphylaxis Community Expert (ACE). The ACE Program seeks to raise awareness, reduce anxiety and minimize the loss of life due to anaphylaxis through their use of education, advocacy and outreach efforts. Ms. Loera values strong family ties and enjoys spending free time with family, friends, and her two dogs. She likes music, the Spurs, HGTV and participating in outdoor activities.

ERICA GOMEZ, MSN, FNP-C | Nurse Practitioner Certified - San Antonio Allergist - Asthma

ERICA GOMEZ, FNP-C | Nurse Practitioner, Certified

Mrs. Gomez joined Allergy SA in September 2014. She is fluent in English and Spanish and is certified by the American Association of Nurse Practitioners. Mrs. Gomez obtained her Master’s of Science degree in nursing with specialization in family nurse practitioner at the University of Texas Health Science in San Antonio (UTHSCSA) in August 2014, and prior to this also received her Bachelor’s of Science degree in nursing at UTHSCSA in 2010.

Mrs. Gomez is a highly motivated individual who has advanced from medical assistant to registered nurse and, now, a family nurse practitioner. She is experienced in treating both pediatric and adult populations. Mrs. Gomez enjoys learning about each of her patients, and strives to provide excellent patient care. In her free time, she enjoys spending time with her family and friends.

Maureen Genov, PA-C | Physician Assistant, Board Certified

Welcoming our newest provider, Maureen Genov, PA-C. She received her bachelor’s degree in Medical Humanities at Baylor University and her Masters of Physician Assistant Studies at the University of Texas Health Science Center.

She is an active member of multiple organizations, such as the Bexar County Physician Assistant Society, the Texas Academy of Physician Assistants, and the American Academy of Physician Assistants. In addition, Ms. Genov has successfully been a part of a study assessing the efficacy of an acute care station at Haven for Hope.

Some of Ms. Genov’s hobbies include hiking, attending Pure Barre classes, watching reality TV shows, and exploring new restaurants and downtown areas.

Ms. Genov will begin taking pediatric and adult patients at the beginning of December 2021.