Is a patient with a history of heavy Ketamine (ketamine) use and recurrent delirium episodes a suitable candidate for eating disorder treatment?

Suitability for Eating Disorder Treatment in a Patient with Heavy Ketamine Use and Recurrent Delirium

This patient should not be admitted to eating disorder treatment until the ketamine-induced delirium episodes are fully resolved and the patient demonstrates sustained psychiatric stability off ketamine for at least several months. The recurrent delirium represents an active, unstable psychiatric condition that would interfere with the intensive psychotherapy that forms the cornerstone of eating disorder treatment.

Primary Concerns with Current Presentation

Active Delirium as a Contraindication

• Recurrent delirium episodes every few months indicate ongoing neurocognitive instability that fundamentally impairs the patient's ability to engage in eating disorder-focused psychotherapy, which is the essential treatment modality for all eating disorders 1.
• The American Psychiatric Association requires that patients have a comprehensive, person-centered treatment plan incorporating psychiatric stability as a foundation for eating disorder treatment 1.
• Delirium represents a severe cognitive disturbance affecting attention, awareness, and cognition that would prevent meaningful participation in cognitive-behavioral therapy, family-based treatment, or interpersonal therapy—the evidence-based treatments for eating disorders 1, 2.

Ketamine Use Complicates Assessment

• While emerging research shows ketamine may have therapeutic potential for treatment-resistant eating disorders when administered in controlled medical settings 3, 4, 5, this patient's heavy oral ketamine use is fundamentally different from supervised ketamine-assisted psychotherapy.
• The patient's substance use pattern with resultant delirium suggests ketamine abuse rather than therapeutic use, which falls under co-occurring substance use disorder 1, 6.
• The American Psychiatric Association acknowledges limited data on eating disorder treatment in patients with co-occurring substance use disorders, but emphasizes that treatment statements should generally apply to these patients—meaning they still require the same foundational psychiatric stability 1, 6.

Required Medical Optimization Before Admission

Psychiatric Stabilization Requirements

• The patient must first achieve complete cessation of ketamine use and resolution of delirium episodes before eating disorder treatment can be effective 2.
• Suicidality and severe psychiatric instability must be assessed and stabilized, as eating disorders have among the highest mortality rates of any mental illness, with 25% of anorexia nervosa deaths from suicide 2.
• The initial psychiatric evaluation must identify all co-occurring health conditions, including substance use disorders, before proceeding with eating disorder-specific treatment 1.

Substance Use Disorder Treatment First

• This patient requires concurrent or sequential treatment for substance use disorder before or alongside eating disorder treatment 6.
• The treatment approach should involve a coordinated multidisciplinary team that addresses both the substance use and eating disorder, but the active delirium must resolve first 6, 2.
• Assessment should include comprehensive metabolic panel, complete blood count, and electrocardiogram to detect medical complications from both ketamine use and the eating disorder 1, 2.

Clinical Decision Algorithm

Step 1: Immediate Assessment

• Conduct comprehensive psychiatric evaluation including frequency, timing, and triggers of delirium episodes 1.
• Obtain detailed ketamine use history: dose, frequency, route, duration of use, and last use 1.
• Perform medical workup: vital signs with orthostatic measurements, complete blood count, comprehensive metabolic panel, and electrocardiogram 1, 2.
• Screen for other substance use and psychiatric comorbidities 1.

Step 2: Stabilization Phase (Required Before ED Treatment)

• Initiate substance use disorder treatment with focus on ketamine cessation 6.
• Monitor for withdrawal symptoms and provide appropriate medical management.
• Document minimum 3-6 months without delirium episodes and sustained abstinence from ketamine before considering eating disorder program admission.
• Maintain psychiatric stability throughout this period with regular monitoring 6, 2.

Step 3: Reassessment for ED Treatment Readiness

• Once delirium-free for sustained period and ketamine abstinent, repeat comprehensive eating disorder assessment 1.
• Confirm patient can engage meaningfully in psychotherapy without cognitive impairment.
• Establish coordinated treatment plan that continues to monitor for substance use relapse while addressing eating disorder 6, 2.

Critical Pitfalls to Avoid

• Do not admit a patient with active, recurrent delirium to an eating disorder program, as they cannot engage in the psychotherapy that is essential for recovery 1, 2.
• Do not minimize the severity of ketamine-induced delirium as a contraindication to intensive eating disorder treatment—this represents serious neurocognitive compromise 2.
• Do not delay addressing the substance use disorder in hopes that eating disorder treatment alone will resolve both conditions—both require specific, evidence-based interventions 6.
• Do not confuse therapeutic ketamine-assisted psychotherapy (administered in controlled medical settings for treatment-resistant cases) with recreational or self-administered ketamine use causing delirium 3, 4, 5.

When Treatment Can Proceed

The patient becomes appropriate for eating disorder treatment only after:

• Complete resolution of delirium episodes for a sustained period (minimum 3-6 months) 2.
• Documented abstinence from ketamine with negative drug screens.
• Demonstrated ability to engage in cognitive tasks and psychotherapy without impairment.
• Establishment of a coordinated treatment plan that includes ongoing substance use disorder monitoring and support 6, 2.

The concerns being raised about this patient's appropriateness for eating disorder treatment are medically and psychiatrically justified—active delirium is incompatible with the intensive psychotherapeutic work required for eating disorder recovery.