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Dr. Melissa Stennett Deuter, MD

Dr. Melissa Deuter is a board certified psychiatrist in San Antonio, Texas and founder of Sigma Mental Health Urgent Care. Dr. Deuter received her undergraduate degree from the University of Arkansas and attended medical school at the University of Arkansas for Medical Sciences. She completed Psychiatry residency at the University of Texas Health Science Center San Antonio and served as Chief Resident in 2003-2004. She is a member of the teaching faculty in the Department of Psychiatry at UTHSCSA School of Medicine and also at the new UIW-COM School of Medicine in San Antonio. She is a former President of the Bexar County Psychiatric Society, a current member of the Texas Society of Psychiatric Physicians (TSPP) Ethics Council, and a current member of the South Texas Psychiatric Physicians Research Network’s Executive Committee. She has been recognized as a San Antonio “Top Doctor” and a “Best of” Doctor, and has received the American Registry “Patient’s Choice Award.” Dr. Deuter has a special interest in urgent psychiatric care and early intervention, new onset psychiatric illness, and differentiating serious illness from normal brain development. She is the author of A Vision for Change: How to Help Someone with Addiction or Mental Illness, a practical guide for families who see signs of mental illness or addiction in a loved one, but don’t know where to begin getting help.

Dr. Deuter is also the author of STUCK in the Sick Role: How Illness Becomes An Identity available on Amazon:


Dr. Sandra Vale, MD

Sandra D. Vale, M.D. is the supervisory behavioral health medical director for Superior Health Plan.  She was previously the Texas Medical Director for Cenpatico Behavioral Health serving Superior Health Plan of Texas.  She was most recently the Medical Director of Adult Behavioral Health at the Center for Health Care Services (CHCS) of Bexar County in San Antonio, Texas.  While at CHCS, she also served as the lead psychiatrist for the Assertive Community Treatment (ACT) program and Intensive Outpatient Commitment Program (IOPC).  In previous years she served as the Chief of Behavioral Health at WellMed Medical Group where she developed an integrated behavioral health program for WellMed’s primary care clinics.  She also served as the director of psychiatry services at the San Antonio State Supported Living Center which works with the intellectually challenged/psychiatrically challenged dual diagnosis adult population.


Dr. Vale is a native San Antonian.  She attended the University of Texas at San Antonio and completed medical school at the University of Texas Health Science Center at San Antonio (UTHSCSA).  Dr. Vale completed her residency training in General Adult Psychiatry at the University of Texas Medical Branch (UTMB) at Galveston where she served as Chief Resident during her final year of residency.  She completed additional Fellowship training in Geriatric Psychiatry at the University of Texas Health Science Center in San Antonio and continues to focus on the geriatric population through her clinical work.  She has received numerous awards and recognition for her clinical care and teaching to most recently include being recognized as one of San Antonio’s top physicians.  Dr. Vale sees herself as a champion for transformation of healthcare systems that are integrated, person centered, and quality focused.


Dr. Phillip Balfanz, MD

Phillip Balfanz, MD MBA is board certified in general and child and adolescent psychiatry. He is the medical director of the Boerne Sigma Mental Health Urgent Care.  Dr. Balfanz attended medical school at UTMB in Galveston and completed residency at UT Southwestern in Dallas. Following his residency he completed a fellowship in child and adolescent psychiatry where he served as Chief Fellow and participated in a community tract through Metrocare Center for Education and Research.  He then served as a child and adolescent psychiatrist for the western 16 counties of Hill Country MHDD and subsequently the medical director for the Linda J. Werlein Crisis Stabilization Unit.  He earned his MBA at the Naveen Jindal School of Management at UT Dallas with a focus on healthcare.

Dr. Balfanz is an active member in several professional organizations. He is a Fellow in the American Psychiatric Association and has served as President for the Bexar County Psychiatric Society, the President-Elect for the Texas Society of Child and Adolescent Psychiatrists, and as a delegate to the Texas Medical Association.  He has experience in helping family members of all ages when illness interferes with a person's mental health and believes in the process of recovery and the power of hope in working toward a healthier life.

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Dr. Christine Masuda, MD

Dr. Christine Masuda is a board certified psychiatrist in Austin, Texas. She received her undergraduate degree from the University of Washington before moving to Texas to serve in Teach for America as a high school science teacher. She attended medical school at the University of Texas Southwestern and completed psychiatric residency at the University of Texas at Austin Dell Medical School.


During her residency, she did a senior selective in psychiatric emergency medicine and saw firsthand the need for more psychiatric urgent care resources. Following residency, she served as a psychiatrist for Harris Health in Houston, where she practiced psychiatry integrated in a family practice setting. 


Dr. Masuda values evidence based medicine and the close partnership of psychiatry with psychotherapy. She completed cognitive processing therapy training which impressed upon her the power in approaching mental illness with multiple modalities.


Caroline Horton, PA-C

Caroline is a Physician Assistant and is nationally certified by the National Commission on Certification of Physician Assistants. She received a Master in Physician Assistant Studies at James Madison University in Virginia and is licensed to practice in the state of Texas by the Texas Medical Board. She has experience in Emergency Medicine and the care of adults and children with acute and chronic mental health disorders in the emergency room setting. She is committed to helping provide mental health services to the people of San Antonio and the surrounding communities that allows more people to access the care they need in an outpatient setting.


Gina Seyfried, PMHNP

Gina Seyfried is a family psychiatric nurse practitioner in the state of Texas with 31 years of Nursing experience, 27 of those years in the Emergency Department.  Gina graduated with her Family Nurse Practitioner certification from Walden University in 2015.  In 2018, she received her Psychiatric Mental Health Nurse Practitioner certification from University of Texas Rios Grande Valley.  She currently works at Center for Healthcare Services and that's where she recognized the need to go back to school to get her certification in Mental Health.  Gina is Passionate about helping individuals dealing with mental health.

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Matthew Dietz, PMHNP

Matthew is a psychiatric mental health nurse practitioner that is board certified by the American Nurses Credentialing Center and is licensed in the State of Texas by the Texas Board of Nursing.  He is a graduate of the University of Texas Health Science Center in San Antonio. Prior to becoming a nurse practitioner, he worked in multiple inpatient mental health facilities as a charge nurse.  He also worked in the home environment with special needs children and adolescents. Matthew believes that a patient-centered, holistic collaborative approach in mental health care is essential in achieving optimal outcomes and building a great therapeutic relationship with those we serve.

Sofia Arras, PMHNP

Sofia Arras is a Psychiatric Mental Health Nurse Practitioner (Board Certified by the American Nurse Credentialing Center). She is Bilingual in Spanish and English. She is licensed by the Texas Board of Nursing with over 16 years of nursing experience in different areas to include critical and medical care, with a Master’s degree in Nursing Education from the University of Texas at El Paso.


Sofia has taught in several universities as an adjunct clinical professor in different states to include Texas, Florida and Colorado. Sofia recognized the need in mental health while teaching and returned to school to receive a Post Master’s in Psychiatry at the University of Texas at Rio Grande Valley. 


She enjoys her calling as a Psychiatric Mental Health Nurse Practitioner with Sigma Mental Health Urgent Care. Sofia believes it’s important to demonstrate compassion, sensitivity, and exceptional communication skills. She believes it is important to see the humanity in everyone and recognize that a person isn’t defined by their mental health condition. Sofia also loves being a nurse and sharing her knowledge with students while preparing them for excellence in nursing.

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Thomas Dietz, PMHNP

Thomas is a psychiatric mental health nurse practitioner that is board certified by the American Nurses Credentialing Center. Prior to becoming a nurse practitioner, he started his career in the healthcare field as a nationally registered paramedic. In 2004 he joined the U.S. Army with a military occupational specialty of health care specialist (combat medic). He served a one-year tour in Iraq from 2008-2009. It was his experience in Iraq which led him to eventually pursue a career in Mental Health. As a registered nurse he worked in both drug research and with a pediatric special needs population.

His practice style involves putting an emphasis on truly listening to his patients. He believes that everyone is unique and treatments are not “one size fits all”. He adopts a holistic health approach that combines medication management along with lifestyle modifications.

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Dr. Margo de la Garza, Ph.D, LPC

Dr. Margo DelaGarza is a psychotherapist in private practice in San
Antonio, Texas. She provides clinical services and mindfulness group
sessions at Sigma Mental Health Urgent Care. Dr. Delagarza is the
author of ‘Mindfulness for a Peaceful Existence’.

Dr. DelaGarza began her career working with adolescents in 1998 and is
experienced in the treatment and assessment of children, adolescents,
and adults struggling with a variety of behavioral and mental health
issues. Dr. DelaGarza specializes in working with high profile clients
and has extensive experience in the treatment of anxiety, depression,
substance abuse, eating disorders, relationship problems, and trauma.
She is trained in several treatment modalities and uses Mindfulness, Eye
Movement Desensitization and Reprocessing (EMDR), Cognitive
Behavioral Therapy (CBT) and Dialectical Behavior Therapy (DBT).

Dr. DelaGarza completed her undergraduate and master’s degrees in
psychology at the University of Texas at San Antonio, where the focus
of her research was on identity development and relationships. She
completed her doctorate in counseling education and supervision at St.
Mary’s University, where her dissertation focused on relationships and
couples satisfaction. She is a Licensed Professional Counselor in the
State of Texas.


Susan D. Sundin, MA, LPC-S

Susan Sundin is a Licensed Professional Counselor with Supervision certification. Susan is currently a psychotherapist in Boerne, Texas with over 7 years of private practice experience and also does educational consulting in school districts throughout Texas.  She has over 25 years’ experience working as a counselor and behavior specialist in public schools. Prior to her work in public schools she was a Licensed Chemical Dependency Counselor and Recreational Therapist working in child and adolescent residential treatment facilities. Susan is a graduate of Texas State University.

Susan’s approach to therapeutic work is based entirely on the relationship that is built between the therapist and the client. She works at providing her clients with a safe and welcoming environment so that they will feel safe in sharing their journey with her. Susan helps her clients understand developmental processes and assists her clients in identifying areas that have hindered their development with the hope that, while working together, they can get the client back on track in their development as a whole person.

Susan specializes in the treatment of anxiety, depression and grief and loss. She has expertise in the area of working with parents of children with special needs, children with behavioral disorders, and young children.


Dexter Brown, LPC

Dexter is a Licensed Professional Counselor who completed his Masters of Science degree in Marriage and Family counseling at Prairie View A&M University.  Dexter currently provides clinical services at Sigma Mental Health Urgent Care and trauma focused equine assistant psychotherapy (TF-EAP) at Courage Ranch.  His focus includes adolescents and families who have been impacted by adverse childhood experiences (ACEs).  There are many forms of trauma which can disrupt an individuals' ability to connect with themselves and others, as well as cause other mental health issues.  He believes creating a safe space and a healthy therapeutic relationship with individuals can create a pathway for healing.  In addition to providing different alternatives to address presenting problems, developing and exploring meaning behind behavior can be empowering.

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