Facebook post by University of Helsinki

Ketamine alleviates depressive symptoms quickly. However, the symptoms often reappear within a week. Neural connections strengthened by the quick treatment of depression are consolidated in the brain during the deep sleep periods of the following night, suggest researchers at the University of Helsinki.
Effects of rapid-acting antidepressants consolidated in sleep? | University of Helsinki helsinki.fi

To prevent the circle of negative thoughts regaining supremacy, depressed patients also need therapy.