About one in three people with major depressive disorder do not respond adequately to two or more antidepressant trials — a clinical pattern known as treatment-resistant depression, and one that standard prescription protocols were not designed to address. That number represents a substantial population of people who have done everything their providers asked of them: tried multiple medications at appropriate doses for appropriate durations, often navigating intolerable side effects and diminishing hope. Treatment-resistant depression is a clinical designation, not a character verdict, and the options for addressing it have expanded meaningfully in recent years.
What Treatment-Resistant Depression Actually Means
Treatment-resistant depression — often abbreviated TRD — has a specific clinical meaning that gets used loosely in everyday conversation. Clinically, TRD refers to a major depressive episode that has not responded adequately to at least two antidepressant medications taken at therapeutic doses for a sufficient duration. This distinction matters because it separates patients who may need a different medication in the same class from patients who may need a treatment that works through an entirely different mechanism.
Several factors contribute to why depression resists standard antidepressants in some patients. Genetic variations in how individuals metabolize medications can mean that standard doses are functionally too low — or cause side effects that prevent reaching a therapeutic dose in the first place. Underlying conditions that sustain depressive symptoms independently of serotonin pathways can blunt the effects of medications designed to address those pathways. And for some patients, the neurological underpinnings of their depression involve systems that SSRIs (selective serotonin reuptake inhibitors) and SNRIs (serotonin-norepinephrine reuptake inhibitors) simply do not directly reach.
At Mend The Mind, we work specifically with adults who have traveled that road and are still struggling. Our evaluation process begins with your treatment history — not your diagnosis in isolation, but the full picture of what you have tried, for how long, at what doses, and how you responded.
Why the Glutamate System Changes the Equation
Most first-line antidepressants work by increasing the availability of serotonin, norepinephrine, or both. For patients with treatment-resistant depression, the research increasingly points to a different system: the glutamate pathway. Glutamate is the brain’s primary excitatory neurotransmitter, and its receptor network plays a central role in synaptic plasticity — the brain’s ability to adapt, form new connections, and regulate mood over time.
Ketamine works by blocking NMDA receptors (N-methyl-D-aspartate receptors) in this system, producing effects that are both faster-acting and mechanistically distinct from every conventional antidepressant most patients with TRD have previously tried. Research supported by the National Institutes of Health shows that IV ketamine therapy produces significant antidepressant effects specifically in patients with treatment-resistant major depression who have not responded to other medications. The speed of that response — often within hours to days, compared to the weeks traditional medications require — is one of the most clinically significant aspects of ketamine therapy for this population.
For patients who have spent months or years cycling through medications with partial responses, intolerable side effects, or no response at all, this mechanistic difference is not a minor detail. It is the reason ketamine may help when other approaches have not.
What the Evidence Shows
The evidence base for ketamine in treatment-resistant depression has grown substantially over the past two decades, moving from early clinical observations to a body of peer-reviewed research that federal health agencies now publicly affirm. The National Institute of Mental Health (2024) has highlighted new research supporting ketamine as a rapid-acting treatment for patients who have not responded to standard care — a federal acknowledgment that reflects the current trajectory of psychiatric research, not fringe advocacy.
Research published through the American Psychiatric Association demonstrates that both single and repeated ketamine infusions can treat treatment-resistant depression, with maintenance protocols extending the duration of benefit for patients who respond to the initial series. This is directly relevant to how we structure care at Mend The Mind. Our standard initial protocol involves six IV infusions over two to three weeks, followed by individually tailored maintenance boosters for patients who benefit from sustained support.
Results vary by individual, and ketamine therapy is not effective for everyone. We do not represent it as a cure. What the evidence supports is that it represents a meaningful, clinically grounded option for a population that has historically had very few alternatives after standard treatments have been exhausted.
What Treatment Looks Like at Mend The Mind
Our approach to ketamine therapy for treatment-resistant depression begins with a thorough evaluation before any treatment is scheduled. We review your complete medication history — which antidepressants you have tried, at what doses, for how long, and what your response was. We screen for factors that can influence medication response, including medical conditions that may be sustaining depressive symptoms through pathways unrelated to serotonin. We discuss what meaningful improvement would look like for you and what realistic expectations for your situation are.
IV ketamine infusions are administered in a private, comfortable treatment room by our founder Cassidy Boyer, a Board Certified Registered Nurse Anesthesiologist and PMHNP candidate completing her post-master’s training at Montana State University. Every session includes continuous vital sign monitoring — heart rate, blood pressure, and oxygen levels — and one-on-one clinical presence throughout. Mental health infusions typically last 40 to 60 minutes, and we stay with you from start to recovery.
For patients who have established a ketamine response and are seeking flexible maintenance support, we also prescribe ketamine troches — at-home dissolvable lozenges that can extend therapeutic benefits between IV sessions. Troches are a practical option for patients managing distance, scheduling constraints, or the practical demands of an intensive in-clinic protocol, and we discuss this option as part of every comprehensive treatment conversation.
Two Barriers We Address Directly
Cost is the most consistent practical concern patients raise before starting treatment, and we believe it deserves a direct answer rather than a footnote. Pricing at Mend The Mind is discussed during consultation rather than published on our website, because treatment plans vary and a single listed figure would not accurately represent what your specific situation involves. We are an out-of-network provider. Through the Osmind care management platform, you receive a detailed superbill following each session that can be submitted to your insurance company for potential reimbursement. Coverage outcomes vary by plan, and we recommend contacting your insurer before starting treatment to understand your out-of-network benefits for ketamine therapy. We are committed to making sure the financial side of treatment is fully understood before you commit to anything.
The second barrier we hear is harder to quantify: the emotional exhaustion that comes from trying treatment after treatment, and the fear that investing hope in something new means risking another disappointment. This is real, and it is one of the most common things patients tell us in their first consultation. We do not dismiss it. We also do not offer false reassurance. What we offer instead is an honest evaluation — a genuine look at your treatment history, a clear explanation of what ketamine therapy involves and what it may and may not offer your specific situation, and a recommendation you can trust because it is based on your actual clinical picture rather than a scripted intake process. Discuss your concerns openly during your consultation. That conversation is part of the care.
Frequently Asked Questions
What makes depression “treatment-resistant”?
Clinically, treatment-resistant depression is characterized by inadequate response to at least two antidepressant medications taken at therapeutic doses for a sufficient duration. If you are unsure whether your experience meets that threshold, we discuss it directly during your evaluation — some patients who have been told they are treatment-resistant have not actually completed a full therapeutic trial, while for others the pattern is unambiguous from their history. Either way, the evaluation process clarifies where you stand.
How quickly does ketamine therapy work for depression?
Many patients with treatment-resistant depression notice meaningful improvement within hours to days of their first infusion — significantly faster than the weeks traditional antidepressants require to show effect. Individual results vary, and some patients require several sessions before experiencing significant relief. A clearer picture of your response typically develops across the full initial six-session series.
Can I continue my current antidepressants during ketamine therapy?
This depends on which medications you take and at what doses. Some medications can continue alongside ketamine therapy; others may benefit from adjustment beforehand. We review your complete medication list during your evaluation and discuss any recommended changes with you. Do not adjust or discontinue any medications without guidance from your prescribing provider.
Is ketamine therapy a long-term solution for treatment-resistant depression?
For some patients, an initial series of infusions produces relief that lasts for months without further treatment. For others, periodic maintenance sessions are needed to sustain the benefits. Research indicates that both initial courses and ongoing maintenance protocols can be effective, and the appropriate approach depends on how you individually respond. We do not apply a standardized schedule — maintenance plans are tailored to your response patterns.
Does Mend The Mind treat depression alongside co-occurring conditions?
Yes. Depression frequently co-occurs with anxiety, PTSD, OCD, and chronic pain, and we treat all of these conditions. If you are managing multiple diagnoses, we account for the full clinical picture during your evaluation and build a treatment plan accordingly.
Key Takeaways
- Treatment-resistant depression is clinically defined as inadequate response to at least two antidepressant medications at therapeutic doses — a specific pattern that signals the need for a different treatment mechanism, not simply a different medication in the same category.
- Ketamine works through the glutamate system — blocking NMDA receptors — rather than serotonin or norepinephrine pathways, making it mechanistically distinct from every antidepressant most patients with TRD have previously tried.
- The National Institute of Mental Health (2024) affirms ketamine as a rapid-acting option for patients who have not responded to standard care, with sustained benefit achievable through maintenance infusion protocols.
- Mend The Mind’s depression treatment structure — six initial IV ketamine infusions over two to three weeks, followed by individually tailored maintenance — aligns directly with the protocols supported in peer-reviewed research.
- Individual results vary. Ketamine therapy is not appropriate for every patient and does not guarantee remission, but for patients with documented treatment resistance it represents one of the most evidence-supported options currently available.
Conclusion
Treatment-resistant depression is one of the most challenging realities in psychiatric care — and it is one of the conditions for which ketamine therapy has the strongest, most consistent evidence. If your depression has not responded to multiple antidepressant trials, that history is clinically informative, not a reason to accept diminished expectations. At Mend The Mind in Livingston, we start every evaluation by taking that history seriously and asking what it tells us about where to go next. Individual results vary, and an honest conversation about your specific situation is where every treatment plan with us begins. To schedule a consultation, call us at 406-350-4439 or reach us through our website.
References
National Institutes of Health. Antidepressant Efficacy in Treatment-Resistant Depression. https://pubmed.ncbi.nlm.nih.gov/23982301/
National Institute of Mental Health. Rapid-Acting Depression Treatment (2024). https://www.nimh.nih.gov/news/science-updates/2024/new-hope-for-rapid-acting-depression-treatment
American Psychiatric Association. Single, Repeated, and Maintenance Ketamine Infusions. https://psychiatryonline.org/doi/10.1176/appi.ajp.2018.18070834
Medical Disclaimer
The information in this blog is for educational purposes only and does not constitute medical advice. Ketamine therapy for treatment-resistant depression should only be pursued under the supervision of a qualified, licensed healthcare provider who is familiar with your full medical and psychiatric history. Individual results vary, and Mend The Mind does not guarantee specific outcomes from any treatment. If you are experiencing a mental health crisis or thoughts of self-harm, please call or text 988 to reach the Suicide and Crisis Lifeline, or go to your nearest emergency room.