A single 40-minute intravenous infusion of esketamine at either 0.20 mg/kg or 0.40 mg/kg produced a rapid and robust antidepressant effect in patients with treatment-resistant depression, with significant improvement in depression scores within two hours. The higher and lower doses were similarly effective, but the lower dose may offer better tolerability. Common side effects included headache, nausea, and transient dissociation that resolved within four hours.
Nitrous oxide, a potent greenhouse gas, is being explored as a treatment for therapy-resistant depression, but its environmental costs are often ignored. A single one-hour treatment produces about 150 kilograms of CO2-equivalents, and a year of treatment for one patient generates roughly 7.8 metric tons of CO2-equivalents. The authors argue that these environmental externalities should be factored into assessments of the therapy's overall value.