Open-label naturalistic study (n≈80) assessing repeated IV (0.5 mg/kg), intranasal, and oral (2.0–2.5 mg/kg) ketamine twice weekly for 4 weeks in patients with treatment-resistant mood disorders.
This prospective naturalistic study evaluates safety, tolerability, and effectiveness of repeated, individually tailored ketamine administered IV, intranasally and orally in inpatients with treatment‑resistant major depressive disorder and bipolar depression.
Dosing regimens include slow IV infusions (0.5 mg/kg over 40 minutes) and twice-weekly intranasal and oral administrations (oral 2.0–2.5 mg/kg), delivered over a 4‑week period; outcomes include clinical response, safety and tolerability measures.
Open-label, individually tailored repeated ketamine dosing delivered IV, intranasal and oral across a 4-week twice-weekly schedule.
Slow IV infusion 0.5 mg/kg over 40 minutes, twice weekly for 4 weeks.
Intranasal ketamine spray, twice weekly for 4 weeks (dose not specified).
Oral solution 2.0–2.5 mg/kg, twice weekly for 4 weeks.
In 42 patients with treatment‑resistant depression, eight adjunctive ketamine infusions produced a statistically significant reduction in anhedonia (SHAPS), and this antianhedonic change mediated ketamine’s antidepressant effect, with one‑week post‑treatment benefits observed only in patients not taking benzodiazepines. These preliminary results require replication in a larger randomised placebo‑controlled trial.