Body Handbook Catalogue Profile Ranking
Psychology BODY HANDBOOK
Psychology ยท ยง464
Ketamine for Depression
It is the first antidepressant that works in hours, not weeks. A single low dose of ketamine cuts depression severity by roughly half within a day for the people who respond, and about half of those who try it respond Zarate 2006. It is for one group: people whose depression has survived two or more antidepressants, about a third of everyone diagnosed. If that's you, this is a real option your psychiatrist can order now.
Decide ยท Course Evidence Moderate Chapter Psychology

It works on a different system. The usual antidepressants raise serotonin and take four to six weeks to do anything. Ketamine acts on glutamate and grows new synaptic connections within 24 hours 1. That is why it is fast, and why one dose can outlast its short half-life by a week.

The response is large and it holds up under a fair test. One low IV dose drops depression severity about 56% at 24 hours, with 71% of people responding and a benefit still there at 7 days 2. The skeptic's objection is that ketamine's dissociation breaks the blind. When tested against midazolam, a sedative that feels like something too, ketamine still won: 64% response versus 28% 3. Head-to-head against electroconvulsive therapy in 403 patients it came out non-inferior, with far less cognitive damage 4. For someone in an active suicidal crisis, symptoms fell within 24 hours 5.

This is a decision to make with a psychiatrist, not a thing to buy online. Ask if you fit: two or more failed antidepressants, no uncontrolled blood pressure, no recent heart attack or stroke, no pregnancy, no active psychosis or mania. Then pick a route.

If you respond, it is fast and unmistakable. The morning after the first dose, the wall isn't there; the loop of "nothing will ever change" loses its grip. Within a week the people who knew you before recognise you again. But this is not one-and-done: without maintenance the effect of a single course fades over one to two weeks. Responders kept dosing had about half the relapse risk of those switched to placebo 6. If two or three doses move nothing, it is unlikely to.

The fine print โ€” when to skip it, and what people get wrong

Skip it with uncontrolled high blood pressure, a heart attack or stroke in the last six weeks, an aneurysm, active psychosis or mania, pregnancy, or a history of ketamine misuse. Flag any new urinary symptoms early; heavy use can damage the bladder 7.

Esketamine isn't a better ketamine; IV racemic has the larger effect, and the spray wins only on approval and coverage. The dissociation is not the point: its intensity doesn't predict the result. Home telehealth troches skip the monitoring and the small-effect oral route.

The commonest failure is stopping after induction feels good; the depression returns within weeks 6. Others: unmonitored home dosing, hidden benzodiazepines, and picking IV when the cash won't last instead of doing the paperwork for the covered spray.

References
  1. 1Li N, Lee B, Liu RJ, Banasr M, Dwyer JM, Iwata M, Li XY, Aghajanian G, Duman RS (2010). mTOR-dependent synapse formation underlies the rapid antidepressant effects of NMDA antagonists. Science. link
  2. 2Zarate CA Jr, Singh JB, Carlson PJ, Brutsche NE, Ameli R, Luckenbaugh DA, Charney DS, Manji HK (2006). A randomized trial of an N-methyl-D-aspartate antagonist in treatment-resistant major depression. Archives of General Psychiatry. link
  3. 3Murrough JW, Iosifescu DV, Chang LC, Al Jurdi RK, Green CE, Perez AM, Iqbal S, Pillemer S, Foulkes A, Shah A, Charney DS, Mathew SJ (2013). Antidepressant efficacy of ketamine in treatment-resistant major depression: a two-site randomized controlled trial. American Journal of Psychiatry. link
  4. 4Anand A, Mathew SJ, Sanacora G, Murrough JW, Goes FS, Altinay M, Aloysi AS, Asghar-Ali AA, Barnett BS, Chang LC, Collins KA, Costi S, Iqbal S, Jha MK, Krishnan K, Malone DA, Nikayin S, Nissen SE, Ostroff RB, Reti IM, Wilkinson ST, Wolski K, Hu B (2023). Ketamine versus ECT for nonpsychotic treatment-resistant major depression. New England Journal of Medicine. link
  5. 5Fu DJ, Ionescu DF, Li X, Lane R, Lim P, Sanacora G, Hough D, Manji H, Drevets WC, Canuso CM (2020). Esketamine nasal spray for rapid reduction of major depressive disorder symptoms in patients who have active suicidal ideation with intent: double-blind, randomized study (ASPIRE I). Journal of Clinical Psychiatry. link
  6. 6Daly EJ, Trivedi MH, Janik A, Li H, Zhang Y, Li X, Lane R, Lim P, Duca AR, Hough D, Thase ME, Zajecka J, Winokur A, Divacka I, Fagiolini A, Cubala WJ, Bitter I, Blier P, Shelton RC, Molero P, Manji H, Drevets WC, Singh JB (2019). Efficacy of esketamine nasal spray plus oral antidepressant treatment for relapse prevention in patients with treatment-resistant depression: a randomized clinical trial. JAMA Psychiatry. link
  7. 7Sanacora G, Frye MA, McDonald W, Mathew SJ, Turner MS, Schatzberg AF, Summergrad P, Nemeroff CB (2017). A consensus statement on the use of ketamine in the treatment of mood disorders. JAMA Psychiatry. link
Related in the handbook (7)
Alternatives
  • โ€” For mild-to-moderate depression, exercise is the free first move; ketamine is for the treatment-resistant end.
  • โ€” If the appeal is an altered state without a drug, holotropic breathwork is the breathing version โ€” far thinner evidence and a long do-not-do list.
  • โ€” Inner work is the durable, non-drug side of treating low mood โ€” often paired with, not replaced by, a fast intervention like ketamine.
  • โ€” Ketamine acts in hours rather than weeks โ€” an option for severe depression while slower-building therapy takes hold.
  • โ€” For depression that's failed multiple drugs, TMS and ketamine are the two main next-line options โ€” different mechanisms, similar goal.
Related
  • โ€” For acute, severe depression with suicidal thoughts, ketamine's hours-not-weeks speed is exactly the gap that matters.
  • โ€” Both are buzzy psychiatric uses of formerly-recreational drugs โ€” but ketamine has real trial backing where microdosing mostly doesn't.
ยท
464