NCT04242914.

Study name	The effect of intravenous ketamine on non suicidal self injuries.
Methods	Double‐blind placebo‐controlled RCT. Assignment: parallel, individual‐level.
Participants	Inclusion criteria: i) females; ii) aged between 18 and 65 years; iii) inpatients on the psychiatric ward of a general hospital; iv) self‐reporting NSSI and/or active NSSI on hospital admission or in the preceding week. Exclusion criteria: i) males; ii) unable to provide written informed consent in Hebrew; iii) pregnant or breast‐feeding; iv) history of substance misuse; v) diagnosed with a psychotic disorder and/or major physical condition, including hypertension, arrthymias, or a severe or active neurological condition; vi) previous treatment involving ketamine in which no improvement was observed.
Interventions	Intervention: intravenous infusion of ketamine (0.5mg/kg) in addition to midazolam (0.03mg/kg) over 40 minutes. Control: intravenous infusion of midazolam (0.03mg/kg) over 40 minutes.
Outcomes	Primary outcome(s): i) NSSI, as measured by the Brief Non‐Suicidal Self‐Injury Assessment. Secondary outcome(s): i) ketamine biomarkers, as measured by levels of interleukin 6, high sensitive C‐Reactive Protein, and brain dendritic neurotrophic factor; ii) depression, as measured by the BDI; iii) anxiety, as measured by the DASS; iv) suicidal ideation, as measured by the C‐SSRS and the BSSI; v) impulsivity, as measured by the BIS‐11; vi) well‐being, as measured by the WHO‐5; vii) NSSI attitudes, as measured by the VAS; viii) adverse effects, as measured by an idiosyncratic scale developed by the authors.
Starting date	25 February, 2019.
Contact information	Principal investigator: Dr Lior Dvorak, Tel‐Aviv Sourasky Medical Center, Tel‐Aviv, Israel (liordv@tlvmc.gov.il).
Notes	We are grateful to Dr Dvorak for confirming the above details were correct, 6 August, 2020.

BDI: Beck Depression Inventory; BIS‐11: Barratt Impulsiveness Scale, 11 item; BSSI: Beck Scale of Suicidal Ideation;C‐SSRS: Columbia Suicide Severity Rating Scale; DASS: Depression Anxiety Stress Scale; kg: kilograms; mg: milligrams; MRI: magnetic resonance imaging; MRS: magnetic resonance spectroscopy; NSSI: non‐suicidal self‐injury; RCT: randomised controlled trial; VAS: Visual Analogue Scale; WHO‐5: World Health Organization, Five Well‐Being Index.