What are the treatment options for a patient with delusional disorder refusing to eat due to delusions of a higher power instructing them to fast?

Treatment of Delusional Disorder with Food Refusal

Immediate Medical Stabilization

This patient requires immediate hospitalization for medical stabilization before any psychiatric intervention can be effective, as refusal to eat constitutes a life-threatening emergency regardless of the underlying psychiatric cause. 1, 2

Critical Initial Assessment

• Measure vital signs immediately: temperature, resting heart rate, blood pressure, and orthostatic changes (pulse and blood pressure), as these patients are at high risk for sudden cardiac death from malnutrition-induced cardiac complications 2
• Document weight, height, and BMI to establish severity of malnutrition 2
• Obtain ECG immediately to assess for QTc prolongation and bradycardia, which predict sudden cardiac death risk in malnourished patients 2
• Order comprehensive metabolic panel including electrolytes (sodium, potassium, chloride, bicarbonate), liver enzymes, and renal function tests to identify life-threatening abnormalities 2
• Check complete blood count to detect anemia and leukopenia from malnutrition 2

Life-Threatening Complications Requiring Hospital Treatment

• Initiate slow, cautious refeeding with phosphorus supplementation to prevent fatal refeeding syndrome in severely malnourished patients 2
• Provide nutrition via nasogastric tube or intravenously if oral intake is insufficient due to delusional refusal 2
• Monitor cardiac status continuously, as up to one-third of deaths in severe malnutrition are cardiac-related, with QTc prolongation and bradycardia being directly related to starvation 2

Psychiatric Treatment Approach

Antipsychotic Medication

Start an antipsychotic medication immediately to address the delusional symptoms driving the food refusal. 3, 4

• Olanzapine is particularly effective for delusional symptoms in the context of severe malnutrition, as it reduces delusions, improves compliance to treatment, and has the added benefit of appetite stimulation 3
• Second-generation antipsychotics (including risperidone, quetiapine, aripiprazole) show positive response rates of approximately 50% in delusional disorder 4
• Pimozide and conventional antipsychotics are alternatives if second-generation agents are not tolerated 4

Psychotherapy Integration

• Initiate psychotherapy once medical stabilization is achieved, as both cognitive-behavioral therapy and psychodynamic approaches show efficacy in delusional disorder 5, 6
• A dynamically oriented therapeutic relationship helps patients gain insight and achieve recovery from psychotic symptoms once the acute medical crisis is resolved 3

Critical Management Considerations

Ethical and Legal Framework

• Apply the principle "in dubio pro vita" (when in doubt, favor life) when the patient lacks capacity to make informed decisions due to delusional thinking 1
• Distinguish this from voluntary refusal of food and drink in patients with capacity—this patient's refusal is driven by delusions, not autonomous decision-making, and therefore requires treatment 1
• Do not delay hospitalization based on patient denial, as this is a life-threatening psychiatric emergency requiring aggressive early intervention 2

Monitoring During Treatment

• Continue cardiac monitoring with serial ECGs, as QTc intervals can worsen during early refeeding 2
• Assess for suicidality regularly, as psychotic disorders carry high mortality risk 2
• Track response to antipsychotic medication by monitoring both delusional content and willingness to eat 3

Common Pitfalls to Avoid

• Do not attempt rapid nutritional rehabilitation, as this increases the risk of fatal refeeding syndrome characterized by electrolyte shifts and cardiac arrhythmias 2
• Do not rely on normal laboratory values to exclude serious illness, as approximately 60% of severely malnourished patients show normal routine laboratory values despite life-threatening malnutrition 2
• Do not treat this as a purely psychiatric problem without addressing medical instability first—the patient must be medically stabilized before transfer to a psychiatric eating disorder program 2