Use of ketamine for acute suicidal ideation in a patient with chronic pain on prescribed cannabinoids.

Ketamine is a standard anaesthetic drug that has been studied as a possible treatment for acute suicidal ideation. Aside to the potential psychotropic effects of ketamine, a Cochrane review reported that available studies suggest a modest effect of ketamine for chronic pain months to years after surgical intervention. We present a patient with acute suicidal ideation who required immediate inpatient psychiatric admission in the setting of concurrent chronic pain on cannabinoids which could not be prescribed within our inpatient hospital setting. This presented a clinical dilemma to rapidly reverse the patient's suicidality while substituting the patient's prescribed cannabinoid products with an alternative pain regimen. Since there is emerging support in the use of ketamine in suicidality and chronic pain, we administered ketamine while withholding cannabinoid products and found evidence to support its use in rapid reversal of suicidal ideation and temporary chronic pain relief.