When someone has already tried more than one antidepressant without much relief, another six- or eight-week wait can feel like a lot. That is where Spravato gets attention. One of the first questions patients usually have is simple: how quickly does Spravato work?
Treatment-resistant depression is not rare. Reviews estimate that roughly 30% of people treated for major depression do not respond adequately after multiple antidepressant trials. Spravato works differently, and changes have appeared much sooner in clinical research. A 2025 randomized trial involving 378 adults with treatment-resistant depression found significant improvement in depression scores about 24 hours after the first esketamine dose compared with placebo.
That does not mean everyone feels dramatically different the next morning. Some notice better motivation early; others need several sessions before the change feels meaningful. The first few weeks are really about watching for a consistent shift.
Spravato is the brand name for esketamine nasal spray. Esketamine is related to ketamine, but the two treatments are not interchangeable. Spravato is FDA-approved for adults with treatment-resistant depression and can be used alone or with an oral antidepressant.
Unlike a daily antidepressant that you take at home, Spravato is used under medical supervision. You administer the nasal spray yourself while a healthcare professional is present, then stay at the clinic for monitoring afterward.
That setup is not just a formality. Dizziness, sedation, feeling disconnected, and temporary increases in blood pressure can occur, so patients are observed for at least two hours before leaving.
Spravato is not necessarily an “easy” treatment. Its appeal is that it gives the care team another option when traditional antidepressants have not done enough.
Most common antidepressants mainly influence serotonin, norepinephrine, or both. Spravato takes a different route.
Esketamine acts on NMDA receptors, which are involved in the brain’s glutamate system. Glutamate is a major chemical messenger involved in communication between nerve cells. You may hear clinicians say that Spravato “targets glutamate.” That is a useful shortcut, although the biology behind its antidepressant effect is still being studied. The FDA describes esketamine as a noncompetitive NMDA receptor antagonist.
The important part for patients is that the mechanism is different from that of many standard medications. That may help explain why someone who has had little success with several antidepressants can still respond to esketamine.
That is also why Spravato is more than “another antidepressant spray.” Its schedule, monitoring, and short-term effects differ from taking a pill at home.
So, how quickly does Spravato work in actual practice?
Some clinical trials have found measurable improvement within 24 hours. In the 2025 JAMA Psychiatry study, both esketamine dose groups showed statistically significant improvement compared with placebo at the day-two assessment, roughly 24 hours after treatment.
Still, “measurable” in a study is not always the same as “obvious” to the person receiving treatment.
A patient may not say, “My depression is gone.” They may say, “I got dressed without sitting on the bed for 20 minutes,” or “I answered a text instead of ignoring everyone.” Early gains can be subtle.
During the induction phase, Spravato is generally given twice a week for four weeks. After that, treatment usually becomes less frequent. Weeks five through eight commonly involve once-weekly sessions. During maintenance phases, appointments may move to weekly or every two weeks depending on response and tolerability.
This is why clinicians look beyond the first dose. A fast early response is encouraging, but the bigger question is whether noticeable improvements continue and become meaningful in day-to-day life. The FDA specifically recommends evaluating therapeutic benefit at the end of the four-week induction period before deciding on continued treatment.
A short symptom log can help. Track sleep, concentration, energy, social interest, and normal tasks. Those details often show progress more clearly than simply writing “better” or “worse.”
Spravato side effects are often most noticeable around the treatment session itself and usually ease as the medication wears off.
Common effects reported in clinical trials include dizziness, nausea, sedation, headache, vertigo, anxiety, vomiting, and dissociation. Dissociation can feel unusual. Some people describe it as feeling disconnected from the room, their body, or the passage of time.
Blood pressure is another reason for close monitoring. It can increase after dosing, so the care team checks blood pressure before treatment and again afterward. Patients are also watched for sedation and breathing problems.
You should plan for the appointment to take up part of your day. After the observation period, someone else needs to drive you home. Driving, operating machinery, or doing anything that requires full alertness should wait until the next day after restful sleep, according to current prescribing guidance.
If side effects are stronger than expected, the treatment team can review timing, dose, other medications, and whether continuing Spravato is appropriate.
Spravato treatment works best when it is treated as a course of care, not a one-time experiment.
For someone asking how quickly does Spravato work, a useful answer is this: some people notice a change within a day, but the first four weeks provide a much better picture of whether the treatment is actually helping.
Spravato is also not the only option for treatment-resistant depression. Depending on the person, a clinician may discuss psychotherapy, medication adjustments, ketamine therapy, or brain-stimulation approaches.
At Scottsdale TMS, patients exploring alternatives can also learn about TMS treatment. TMS does not use a psychoactive medication or require a two-hour post-dose observation period. Instead, it uses targeted magnetic pulses to stimulate areas of the brain involved in mood regulation.
Choosing between Spravato and TMS treatment is not about which sounds more advanced. It comes down to treatment history, medical needs, schedule, comfort with side effects, and what the care team believes is most appropriate.
Dr. Vines has practiced psychiatry in Arizona for for over 25 years and has experience working with diverse populations that include children, adolescents, adults, geriatrics, SMI patients, and the chemically dependent.
August 21, 2026
