Your antidepressant may be doing exactly what it was designed to do. SSRIs and SNRIs increase serotonin or norepinephrine availability in the synaptic cleft. Research shows that fewer than 40% of patients with major depression achieve remission with their first antidepressant. That means the majority of patients will need a different approach, and for many, that means a different mechanism entirely.

Susannah Dowling is a board-certified Psychiatric-Mental Health Nurse Practitioner at Axis Integrated Mental Health in Denver who specializes in exactly this problem: patients whose depression has not responded adequately to standard pharmacotherapy.

She is trained in the advanced treatment modalities that target different neurobiological pathways, including transcranial magnetic stimulation (TMS), which uses focused magnetic pulses to stimulate the prefrontal cortex; esketamine (Spravato), which works through NMDA receptor antagonism to restore glutamatergic signaling; and ketamine-assisted therapy.

These are not alternative or experimental treatments. TMS is FDA-cleared for major depressive disorder and OCD. Spravato is FDA-approved for treatment-resistant depression. Both are covered by most major insurance plans when clinical criteria are met.

Not sure whether TMS or Spravato is covered by your plan? Axis offers free financial consultations to verify your benefits before your first appointment. Call (720) 400-0505.

Why Her Diagnostic Training Changes What Treatment Looks Like

Most psychiatric providers prescribe from a standard formulary. Susannah also diagnoses at a level most prescribers cannot.

She is trained and certified in the ADOS-2 (Autism Diagnostic Observation Schedule, Second Edition) and the ADI-R (Autism Diagnostic Interview-Revised), the gold-standard instruments for Autism Spectrum Disorder assessment. She has administered these evaluations independently and as part of interdisciplinary teams at the Kennedy Krieger Institute, one of the country’s foremost centers for neurodevelopmental research and treatment. She has also used the Vineland-3 for adaptive behavior assessment across clinical and educational settings.

This matters because psychiatric symptoms do not exist in isolation. A patient presenting with treatment-resistant depression may have an undiagnosed neurodevelopmental condition shaping their symptom profile and their medication response. A child whose anxiety is not improving on standard treatment may have sensory processing differences that change the entire clinical picture. Susannah can identify these patterns because she has the diagnostic tools to look for them, not just the prescriptive tools to treat what is on the surface.

That combination, advanced diagnostic capability paired with advanced treatment modalities, is rare. In the Denver psychiatric market, the overlap between providers who can administer the ADOS-2 and providers who can prescribe TMS and Spravato is vanishingly small. Susannah sits at that intersection.

Published Research and Academic Contributions

Susannah is a co-author of “Pharmacotherapy of emotional and behavioral symptoms associated with autism spectrum disorder in children and adolescents,” published in Dialogues in Clinical Neuroscience (2017). The paper examines evidence-based pharmacological approaches for managing aggression, irritability, and anxiety in paediatric patients with ASD, a population she has worked with extensively throughout her career.

She also held a joint faculty appointment at the Johns Hopkins University School of Nursing, where she provided clinical and didactic instruction to graduate students in the PMHNP and post-master’s certificate programs. She designed curricula, supervised clinical rotations, and mentored the next generation of psychiatric nurse practitioners. Several of the PMHNPs practicing in the mid-Atlantic region today were trained, in part, by Susannah.

Systems-Level Thinking Applied to Your Individual Care

Susannah earned her Lean Six Sigma Green Belt and applied it to psychiatric care delivery, not in the abstract, but in measurable operational improvements. She redesigned end-to-end clinical workflows, built onboarding systems for new PMHNPs, and created data-driven performance tracking that improved provider productivity and documentation efficiency. She designed and launched a best-practice initiative for attending psychiatrists in the private-pay sector with projected annual revenue impact of approximately four million dollars.

At Axis Integrated Mental Health, that systems-level thinking shows up in how your care actually works. Your first appointment is not rushed through a 15-minute intake slot. Your provider, your therapist, and your primary care physician are in communication with each other proactively. Insurance questions get answered before they become barriers. Medication refill requests do not disappear into a void. The operational infrastructure exists so that clinical decisions can focus on clinical quality, not administrative firefighting.

If you have been in a practice where logistics got in the way of treatment, you know how much the systems behind the care matter. At Axis, our team handles the insurance verification so you can focus on getting better. Schedule a free financial consultation: (720) 400-7025.

Who Susannah Works With

Susannah treats children, adolescents, and adults across the full spectrum of psychiatric and neuropsychiatric conditions: major depressive disorder and treatment-resistant depression, generalized anxiety disorder and panic disorder, PTSD and complex trauma, bipolar I and bipolar II disorder, Autism Spectrum Disorder (diagnostic evaluation and ongoing management), ADHD (assessment and pharmacological treatment), co-occurring psychiatric and neurodevelopmental conditions, burnout and occupational stress syndromes, and emotional and behavioral symptoms in pediatric patients with developmental disabilities.

She is deeply committed to expanding access for patients in underserved and marginalized communities, including those who have faced dismissive care, insurance barriers, or diagnostic complexity that previous providers were not equipped to address.

Training and Credentials

• BSN, Johns Hopkins University School of Nursing.
• MSN, Vanderbilt University School of Nursing.
• NP clinical training, Johns Hopkins Medical Institutions.
• MA in Counseling Psychology, University of North Florida.
• BA in English, Sewanee: The University of the South.
• Board-certified by the American Nurses Credentialing Center (ANCC).
• Lean Six Sigma Green Belt, Maryland Patient Safety Center.
• Published in Dialogues in Clinical Neuroscience. Faculty Associate (Lecturer and Clinical Instructor), Johns Hopkins University School of Nursing (2016-2020).
• Clinical roles at the Kennedy Krieger Institute (2015-2019), Sheppard Pratt (2021-2025), Mountain Area Health Education Center (2020-2021), and SMA Healthcare (2019-2020). Active Colorado prescriptive authority (psychiatric-mental health).

The Person Behind the Credentials

“I have always been drawn to understanding people,” Susannah says. “How we think, feel, and make meaning of our experiences. Mental health felt like the natural intersection of science, story, and human connection.”

Before nursing, she studied English and Counseling Psychology. She credits that interdisciplinary background with shaping how she communicates with patients and families: not in jargon, not in clinical shorthand, but in language that respects the intelligence and experience of the person sitting across from her. Outside the clinic, she is settling into Denver life with her dog, spending time at her niece’s dance studio, and hunting for hidden gems at Colorado thrift stores. She describes thrifting the same way she describes clinical work: “Noticing what is overlooked, paying attention to detail, and seeing potential others might miss.”

Schedule an Appointment or a Free Financial Consultation

Susannah is accepting new patients at Axis Integrated Mental Health in Denver. If your current treatment is not giving you the results you need, or if you want to understand whether advanced options like TMS or Spravato might be appropriate and what your insurance covers, the next step costs you nothing.

Call (720) 400-7025 to book an appointment or schedule a free financial consultation. Our team will verify your benefits and walk you through your options before your first session. No commitment. No surprises.