A Clinician’s Framing
One of the most clinically interesting shifts in the last decade is not just that ketamine can help certain patients with treatment-resistant depression. It is that the same medication has a history in anesthesiology and pain medicine, and it continues to be studied and used across both pain and mood contexts, with overlapping questions about mechanisms, patient selection, and safe implementation.¹⁻⁴
At the same time, it is exactly this “promise + complexity” combination that makes standards and restraint important. This is not casual medicine.
Why Pain and Mood So Often Travel Together
Chronic pain and mood symptoms frequently co-occur and reinforce each other through function, sleep disruption, stress physiology, and central nervous system changes. Reviews and research on pain–mental health comorbidity emphasize this close association and the social and clinical consequences that follow.⁵
Clinically, this shows up as:
- Pain that escalates when depression and anxiety escalate.
- Depression that becomes more treatment-resistant when pain remains uncontrolled.
- Functional decline that is driven more by the whole system than by a single diagnosis.
What’s “Emerging” Right Now
TRD implementation maturity
In TRD, expert groups synthesize evidence and focus heavily on implementation details: appropriate setting, infrastructure, personnel, and monitoring.¹ CANMAT similarly emphasizes that single-dose IV racemic ketamine has strong efficacy evidence in TRD, while maintenance evidence is more limited, and risks need case-by-case assessment.³
Complex pain protocols and consensus standards
In pain medicine, consensus guidelines exist for IV ketamine infusions in chronic pain, including patient selection, contraindications, and safety considerations.²
This matters because pain protocols can differ from mood protocols, but standards still apply: screening, monitoring, and a clear rationale for why ketamine is being used in this patient at this time.
The “shared mechanism” conversation
A cautious version of the emerging conversation is that glutamatergic systems and neuroplasticity are relevant in both chronic pain and mood disorders. That does not mean every patient with both conditions is a good candidate. It means clinicians should think in terms of systems and circuits, not siloed diagnoses. Evidence syntheses for mood disorders emphasize this paradigm shift while still highlighting unresolved questions and the importance of safety.¹⁴
How I Think About Candidate Selection When Pain and Mood Overlap
Start with the clinical objective
- Are we aiming to reduce depressive symptoms that have not responded to standard care?¹³
- Are we aiming to reduce a refractory pain syndrome where other evidence-based options have been insufficient?²
- Are we aiming to restore function in a patient with multidimensional pain–mood impairment?
Confirm the basics before escalation
Ketamine should not replace foundational care: appropriate antidepressant trials, psychotherapy access, sleep assessment, physical rehabilitation, and coordinated pain management when indicated.¹³⁵
Use contraindications and risk flags as guardrails
Pain consensus guidance highlights contraindication categories (for example, poorly controlled cardiovascular disease, pregnancy, psychosis).² Mood disorder implementation guidance emphasizes safety and tolerability concerns and the need for competent monitoring infrastructure.¹³
Responsibility When People Are Desperate
Some of the most ethically challenging cases are not the straightforward TRD referrals. They are patients with long-standing pain, worsening mood, and real functional collapse.
My bias is that desperation is not an indication. It is a reason to slow down, screen carefully, coordinate more tightly, and choose a setting that can monitor responsibly. FDA warnings about compounded ketamine for psychiatric indications underscore why setting and monitoring cannot be treated as a convenience variable.⁶
What I Want Referring Clinicians to Take Away
- Ketamine sits at a real intersection of anesthesiology, pain medicine, and psychiatry, and implementation details are the difference between “care” and “risk.”¹⁻³
- Pain and mood overlap is common and clinically meaningful, but it does not eliminate the need for careful selection.⁵
- Responsible practice is possible through screening, monitoring, and coordinated care.
References
- McIntyre RS, et al. “Synthesizing the Evidence for Ketamine and Esketamine in TRD: Expert Opinion on Evidence and Implementation.” Am J Psychiatry. (2021).
- Cohen SP, et al. ASRA/AAPM/ASA consensus guidelines on IV ketamine infusions for chronic pain. (2018).
- Swainson J, et al. CANMAT Task Force Recommendations for racemic ketamine in adults with MDD. (2021).
- Sanacora G, et al. “A Consensus Statement on the Use of Ketamine in the Treatment of Mood Disorders.” JAMA Psychiatry. (2017).
- Bhatt K, et al. “The pain and mental health comorbidity.” (2024).
FDA warning on compounded ketamine products for psychiatric disorders. (Oct 10, 2023).
