Source: Robby Berman, Medical News Today
The strongest effect that the studies document is the value of intravenous ketamine therapy for relieving depression.
A reduction in unipolar depression severity occurred within anywhere from 1 to 24 hours, and it lasted for 1–2 weeks. In comparison, oral doses took up to 2 weeks to have an effect.
Bipolar depression relief was also rapid, occurring as quickly as 4 hours after administration and consistently by 24 hours. The full effect lasted for up to 3 days, with some relief still apparent after 7 days.
The studies also support the use of ketamine for treating affective disorders and thoughts of suicide.
Of suicidal ideation, co-author and University of Exeter Ph.D. candidate Ozden Merve Mollaahmetoglu told Medical News Today:
“It is really interesting that there is some evidence of an effect on suicidal thoughts independent of depressive symptoms, and it would be great to understand the mechanism of this effect. This finding is important because there is a risk of suicide in several mental health problems, so it would be interesting to see if we could treat suicidal thoughts in other conditions, such as substance use disorders.”