1) Psychiatric

• Lack of clear indication for KAT (e.g. a client is applying only out of personal interest, as a result of a personal journey, seeking new experiences, currently in spiritual bypass, etc.).
• Diagnosis of schizophrenia, schizoaffective disorder, delusional disorder, clinically severe bipolar disorder with manic episodes and psychotic symptoms, and/or any other psychotic disorder (except toxic or drug-induced psychosis) in the client’s medical history.
• Increased susceptibility to develop psychosis as determined by the client’s clinical record, psychiatric examination, and family history (occurrence of psychosis of the F.2x type in first-degree relatives).
• Active substance addiction other than tobacco addiction (F17.x), unless abstinent for at least 1 year. This criterion does not apply to patients who are currently undergoing institutional treatment for their addiction and are completely abstinent, as confirmed by repeated negative drug tests. KAT may be administered if the physician treating the client’s addiction approves.
• Severe personality disorder that would prevent or significantly interfere with the patient’s cooperation in this form of treatment (especially of the paranoid and borderline types). Exceptions include a comorbid personality disorder (e.g. with depression) or cases in which KAT is intended as a supportive treatment for the personality disorder itself, as long as at least partial evidence for such use can be found in the literature. Such cases may warrant a consultation with other Psyon psychiatrists.
• Regular use of psychotropic drugs that may interact with the effects of ketamine, unless these are discontinued 4 elimination half-lives prior to ketamine administration (these include primarily opioids such as tramadol, MAOIs and other antidepressants, and benzodiazepines), at the discretion of the examining psychiatrist.
• Severe clinical risk of suicidality: If the client has specific suicidal ideation with the intent to act on it (requiring an intervention and hospitalization) and/or has made a serious suicide attempt in the past 6 months (as assessed by a psychiatrist).

2) Somatic

• Pregnancy and lactation.
• Severe cardiovascular disease: World Health Organization (WHO) stage 2 or higher arterial hypertension or decompensated stage 1 arterial hypertension, hemodynamically significant heart defect, and other types of severe cardiovascular disease (e.g. cerebrovascular accident, myocardial infarction, and clinically significant arrhythmia in the past year).
• Uncontrolled or insulin-dependent diabetes mellitus.
• Acute hepatitis infection or severe impairment of liver function.
• History of intracranial hypertension, glaucoma, pre-eclampsia, or eclampsia.
  
• Untreated or inadequately treated thyroid disease.
• Epilepsy.
• Other serious somatic conditions as determined by the examining physician in consultation with an internist and/ or anesthesiologist.
  
• Any acute infection or recent respiratory infection associated with a risk of laryngospasm.
• History of allergic reactions to ketamine.
• Regular use of medications that may interact with the effects of ketamine, as determined by the examining physician.
• Consumption of grapefruit juice (20 hours prior to the ketamine session) and/or St. John’s wort (one week prior to the ketamine session).