Team

Calysta Tilley, PA-C, CAQ-Psych, is a certified Physician Assistant with a focused dedication to psychiatry and mental health. Her clinical interests include anxiety disorders, mood disorders, and perinatal and postpartum psychiatry, where she blends evidence-based care with a strong focus on supporting overall patient well-being.

A native of rural southeast Georgia, Calysta earned her Bachelor of Science in Biology from Georgia College in Milledgeville, followed by a Master of Physician Assistant degree from Augusta University (formerly the Medical College of Georgia). While pursuing her graduate studies, she was awarded the Wendy Cline Paschal Service from the Heart Scholarship in recognition of her exceptional compassion and commitment to patient care.

Calysta’s early career was shaped by her work in community mental health at Gateway Community Service Board, where she provided crisis stabilization and outpatient care for individuals with complex psychiatric conditions, including mood and psychotic disorders. In addition, she has experience in ketamine infusion therapy, offering innovative treatment options for patients with treatment-resistant depression and other complex mood disorders, combining advanced approaches with compassionate support. These experiences continue to inform her patient-centered approach to care.

Outside of the clinic, Calysta enjoys traveling, doting on her ever-growing collection of houseplants, loving her rescue animals (two cats and her dog, Olive), and spending time with her husband.

Dr. Paige Marnell is a board-certified physician in General Psychiatry and Addiction Medicine, driven by a passion for transforming mental health and addiction care. She completed her psychiatry residency at the University of Chicago and an Addiction Medicine fellowship at the University of Texas Southwestern, building a foundation for a career dedicated to innovative, patient-centered treatment and advocacy.

A passionate advocate for harm reduction and equitable access to care, Dr. Marnell spearheaded Chatham County’s first community-based harm reduction program and continues to champion widespread access to medication for opioid use disorder (MOUD), ensuring that all individuals in need can receive life-saving treatment.

Committed to education and mentorship, Dr. Marnell served as Program Director for the Addiction Medicine Fellowship she helped establish at Gateway Community Service Board. In this role, she guided and taught residents on the complexities of addiction treatment, helped shape the curriculum, mentored emerging physicians, and fostered a culture of compassionate, evidence-based care. Her leadership has been instrumental in training the next generation of addiction specialists and advancing the field within her community.

Her leadership extends beyond clinical practice. She has served on the Board of Trustees for the Georgia Psychiatric Physicians Association and currently holds faculty appointments as Assistant Professor in the Department of Psychiatry at both Mercer University School of Medicine and the Medical College of Georgia.

Dr. Marnell calls the charming city of Savannah, home, where she loves spending time with her husband, their two daughters, and their playful dog, Holly.