Spravato can begin improving depressive symptoms within hours of the first dose. In clinical trials, patients showed measurable improvement on depression rating scales as early as 4 hours after their initial treatment, with statistically significant gains at the 24-hour mark. That said, the full therapeutic benefit builds over weeks, and the treatment follows a structured schedule designed to deepen and stabilize your response over time.
What Happens in the First 24 Hours
Spravato works faster than any traditional antidepressant. In the ASPIRE trials, which studied patients with major depression and active suicidal thoughts, depression scores improved significantly within 24 hours of the first dose. Across multiple Phase 3 trials, benefits emerged within hours and were clinically meaningful, not just statistically detectable.
This doesn’t mean you’ll feel completely better after one session. What patients typically experience is a noticeable lift, a partial easing of the heaviness. Remission rates after the first dose ranged from 27% to 50% across pooled trial analyses, meaning some people do reach full symptom relief quickly, but most need continued treatment to get there.
Why It Works So Much Faster Than SSRIs
Traditional antidepressants increase serotonin availability and then wait for the brain to slowly adapt, which is why they take 4 to 6 weeks to kick in. Spravato takes a completely different route. It blocks a specific type of receptor in the brain, which triggers a surge of glutamate, the brain’s primary excitatory chemical messenger.
That glutamate surge sets off a chain reaction: it increases the production of a growth factor that helps neurons strengthen their connections, and it rapidly rebuilds tiny branch-like structures on nerve cells (called dendritic spines) that had been lost during prolonged depression. Research from Yale demonstrated that this regrowth begins quickly, which is why mood can shift within hours rather than weeks. Scientists believe the initial mood lift comes from enhanced signaling between neurons, while the longer-lasting benefit comes from those physically rebuilt connections stabilizing over time.
The 4-Week Induction Phase
During the first four weeks, you receive Spravato twice per week. This is the induction phase, where the treatment is building momentum. By the end of week four (Day 28), the TRANSFORM-2 trial found that 69% of patients on Spravato met the threshold for clinical response, compared to 52% on placebo. In TRANSFORM-1, response rates were 53% to 54% depending on dose, versus 39% for placebo.
Each session takes place in a certified healthcare setting. You self-administer the nasal spray under supervision, then stay for at least two hours of monitoring. During that window, your care team checks your blood pressure (which peaks around 40 minutes after dosing and typically returns to normal within about 90 minutes) and watches for sedation or dissociation.
What the Monitoring Window Feels Like
The two-hour observation period exists because Spravato causes temporary side effects that need to resolve before you can safely leave. In clinical trials, 49% to 61% of patients experienced some degree of sedation, and 61% to 75% experienced dissociative or perceptual changes like distortions of time or space, feelings of unreality, or a sense of detachment from yourself. These effects sound dramatic, but they’re transient. Most side effects begin shortly after dosing and resolve within 90 minutes.
Blood pressure rises are common and peak at roughly the 40-minute mark. At least 95% of blood pressure changes occurred and resolved on the same day, with values typically returning to pre-dose levels by the 90-minute check. You should avoid eating for at least two hours before your appointment and stop drinking liquids 30 minutes before, since nausea and vomiting can occur.
Weeks 5 Through 8 and Beyond
After the four-week induction, treatment shifts to once weekly for weeks five through eight. After that, dosing is individualized based on how your depression is responding. Some people move to every-other-week sessions during long-term maintenance.
Continuing treatment matters. In the SUSTAIN-1 relapse prevention trial, patients who had achieved a stable response and then stopped Spravato relapsed at more than double the rate of those who continued: 57.6% relapsed on placebo versus 25.8% on ongoing Spravato. For patients in stable remission, continuing treatment cut relapse risk by 51%. For those who had achieved stable response (improved but not fully remitted), the risk dropped by 70%.
Factors That Affect How Quickly You Respond
Not everyone responds on the same timeline, and researchers have identified several factors that predict a faster or slower response. People who had been in their current depressive episode for a shorter time tended to respond better by the six-month mark. Those with fewer additional psychiatric conditions (like anxiety disorders or substance use issues) also fared better. Higher baseline depression severity and benzodiazepine use were linked to delayed responses in both traditional analyses and machine-learning models.
Spravato is always prescribed alongside an oral antidepressant, not as a standalone treatment. The clinical trials that led to its approval all studied it in combination with a standard antidepressant, so the results reflect that pairing. The rapid early effects come from Spravato, while the oral medication provides a foundation of ongoing support as Spravato sessions become less frequent over time.
A Realistic Timeline to Expect
Here’s a practical summary of what the evidence shows:
- Hours 4 to 24: Measurable improvement in depression scores. Some patients notice a meaningful shift in mood.
- Week 4: Roughly 53% to 69% of patients meet clinical response criteria, depending on the trial and dose.
- Weeks 5 to 8: Treatment frequency drops to weekly as gains consolidate.
- Months 3 to 6 and beyond: Ongoing maintenance sessions help sustain improvement. Stopping treatment significantly increases relapse risk.
The speed of initial relief is what sets Spravato apart from other antidepressants. But the full picture includes weeks of structured treatment to stabilize that early response into lasting improvement.