Kyra Munzenmaier, MD

Dr. John Lundeen earned his medical degree from the Medical College of Georgia and completed his psychiatry residency at TriStar Centennial Medical Center. He has worked with adults of all ages in both outpatient and inpatient settings, bringing a wide range of experience to his practice.

Dr. Lundeen approaches every patient with respect, empathy, and a genuine desire to understand their unique experience. He recognizes that seeking treatment can be intimidating and strives to create a welcoming, non-judgmental environment where patients feel safe and heard.

Dr. Lundeen believes in a collaborative treatment process, prioritizing each patient’s goals, values, and input. He emphasizes mental health education as a core component of care, empowering patients to better understand their treatment options and take an active role in their well-being.

Dr. Sara Mateo holds the position of staff Psychiatrist at Talkiatry. She is a board-eligible adult Psychiatrist. Dr. Mateo completed her Medical degree at the University of Benghazi- Faculty of Medicine and finished General Psychiatry Residency training at Tower Health/DrexelPhoenixville Hospital. Throughout her career, Dr. Mateo has actively contributed to various leadership roles and committees, demonstrating her commitment to advancing medical education and promoting diversity in the field. During her training, she generously shared her knowledge through educational presentations and lectures, fostering the growth of fellow trainees and medical students. Dr. Mateo is dedicated to creating a therapeutic environment characterized by warmth, empathy, and nonjudgmental support. Her approach involves collaborating with patients to develop individualized treatment plans that consider cultural, biological, psychological, and social factors. With a primary focus on medication management, Dr. Mateo's keen interest in psychotherapy is evident, as she often integrates supportive therapy, cognitive behavioral therapy, and psychodynamic psychotherapy during 30-minute follow-up visits to optimize wellness and recovery. Dr. Mateo brings a wealth of experience in caring for individuals of diverse ages and backgrounds, adeptly addressing a wide spectrum of conditions. Her expertise extends to treating depressive disorders, bipolar disorders, anxiety disorders, trauma and stress related disorders, ADHD, OCD, Insomnia, psychotic disorders; she also has experience treating individuals with medical comorbidities.

Dr. Kristin Ratz is a Board-Certified psychiatrist who is an expert in the diagnosis, treatment, and prevention of mental, emotional and behavioral disorders. She specializes in medication management combined with supportive therapy during 30-minute follow-up sessions. Dr. Ratz recognizes that each patient is unique and believes in an environment of collaboration, in which the patient and psychiatrist work together in order to develop the best individualized treatment plan. A California local, Dr. Ratz obtained her undergraduate education at University of California, Davis, graduating magna cum laude with a degree in Human Development. She then attended medical school at Loma Linda University School of Medicine, obtaining her Medical Doctorate. Following this, she completed her adult psychiatry residency training at the distinguished University of California, Irvine. Dr. Ratz has worked in a diverse range of healthcare settings, including county and community clinics, and is very experienced in telepsychiatry. She pays close attention to not only an individual's emotional state, but also their physical, spiritual, and social well-being, in order to provide her patients with exceptional holistic care.

Mahreen Rashid, PMHNP, has over ten years of experience treating patients with a variety of psychiatric diagnoses across inpatient, intensive outpatient, and outpatient settings. While she has cared for children, adolescents, and adults, her primary focus and passion is supporting adults with their mental health needs. She earned her medical degree and completed her training with a commitment to compassionate, evidence-based care.

Mahreen takes a collaborative approach, working closely with each patient to understand their emotional needs and medication preferences. She values a team-based approach, integrating input from patients and other care providers to create a holistic treatment plan that supports overall well-being.

During initial evaluations, Mahreen gathers a thorough history, including medical background, mental health concerns, and personal goals. She reviews past medication trials, discusses previous experiences with providers, and assesses each patient’s comfort level with new treatments. Together, she and her patients develop individualized plans to support long-term mental health and wellness.

Dr. Kathryn Bertacchi is board-certified in both adult and child & adolescent psychiatry. Originally from California, she earned her medical degree from University College Cork in Ireland and completed residency and fellowship at Emory University. She has practiced in varied settings, including developing specialized clinics in eating disorders and gender-affirming care. She is a member of several professional organizations including AACAP, APA, and WPATH.

Dr. Bertacchi fosters an inclusive, nonjudgmental environment where patients feel safe to be themselves. She approaches care with curiosity, compassion, and deep respect for each person’s unique story, aiming to help individuals feel genuinely heard and supported throughout their treatment journey.

In early sessions, Dr. Bertacchi works collaboratively to understand patients' lives, goals, and challenges. While her focus is medication management, she integrates cognitive-behavioral, humanistic, and supportive techniques. She may recommend additional therapy as needed and particularly values working with youth and adults from diverse backgrounds.

Serena Mirchandani is a board-certified psychiatric nurse practitioner with extensive experience treating serious mental illnesses such as bipolar disorder and schizophrenia spectrum disorders. She also provides care for individuals with depression, anxiety, PTSD, OCD, autism spectrum disorder, and substance use disorders. Serena earned both a Master of Science in Nursing and a Doctorate in Nursing Practice in psychiatry from Columbia University. She completed a Nurse Practitioner Fellowship at Community Healthcare Network and worked at Bellevue Hospital for 2.5 years, providing care on an inpatient psychiatric unit for a diverse, underserved population.

Serena’s approach is grounded in open communication, evidence-based care, and deep respect for each patient’s lived experience. She prioritizes a collaborative, safe space where individuals feel heard, respected, and empowered. Her holistic style supports honest conversation, transparency in treatment options, and patient-centered goals.

Serena begins with a comprehensive assessment to understand each patient's full story—biological, psychological, and social. She then partners with patients to develop personalized, evidence-based treatment plans that align with their values and goals. She emphasizes education, transparency, and regular follow-up to support ongoing progress and informed decision-making.