Up To 72% Of People On Ketamine Therapy End Their Depression

Nobody actually knows the exact remission rate for ketamine therapy—because it depends on how it’s given (IV, injection, nasal spray), how long someone stays in treatment, and how many sessions they complete. Most IV ketamine studies stop after just one or two doses. That’s not how ketamine therapy works in real life.

Our goal was to cut through the noise—contradictory studies, incomplete protocols, one-off success stories—and give you a realistic, side-by-side estimate of what remission might look like when ketamine therapy is delivered as it’s actually intended. That’s what the table below is for.

It shows how we estimated up to 72% remission for IV ketamine with therapy, and up to 49% for Spravato. Each figure is based on a full review of 33 systematic reviews and meta-analyses, not cherry-picked studies. And each estimate reflects conservative, evidence-based modeling—not inflated promises.

IV Ketamine vs. Spravato: Remission Rate Summary

Remission Rate Comparison Table

Why IV Ketamine Outperforms Spravato

Research indicates IV ketamine is 2-5 times more effective than Spravato (esketamine nasal spray) for treating depression. Systematic reviews show IV ketamine achieving 27-43% remission rates after just 1-2 infusions, while statistical modeling projects up to 72% remission with a full protocol plus therapy. By comparison, Spravato reaches 32-58% remission (median 39%) with complete treatment, or approximately 49% when combined with therapy.

This significant effectiveness gap can probably be explained by three key factors:

1. Why Does IV Ketamine’s 100% Bioavailability Lead to Better Depression Treatment?

IV ketamine achieves 100% bioavailability, delivering the entire medication dose directly into the bloodstream. Every molecule reaches its target in the brain without loss or variation between treatments.

In contrast, Spravato’s nasal spray has only about 48% bioavailability, meaning less than half the medication enters the bloodstream. This absorption rate can fluctuate further due to nasal congestion, allergies, sinus problems, or improper administration technique, creating inconsistent therapeutic effects between sessions.

2. How Does Weight-Based Ketamine Dosing Improve Depression Outcomes Compared to Fixed Doses?

IV ketamine utilizes weight-based dosing (typically 0.5 mg per kilogram), ensuring treatment is precisely tailored to each patient’s physical characteristics. This personalization maximizes effectiveness while minimizing the risk of under or overdosing.

Providers can also make incremental adjustments (as small as 0.1 mg/kg) based on individual response, allowing them to find the optimal therapeutic level for each patient. If someone gains or loses weight, the dose can be recalibrated accordingly.

Spravato offers only two fixed doses (56 mg or 84 mg) regardless of the patient’s weight, metabolism, or response. This one-size-fits-all approach means a 120-pound person receives the same dose as someone weighing 200 pounds, potentially leading to suboptimal treatment outcomes.

3. What Makes Full-Spectrum Ketamine More Effective Than Spravato’s Single-Molecule Approach?

IV ketamine contains both R-ketamine and S-ketamine enantiomers (mirror-image molecules), providing a complete therapeutic profile. Research suggests these components work synergistically:

• S-ketamine offers rapid symptom relief through NMDA receptor antagonism
• R-ketamine appears to provide longer-lasting antidepressant effects with fewer dissociative side effects, potentially through enhanced neuroplasticity

Spravato contains only S-ketamine, excluding the potentially crucial contributions of R-ketamine. This limitation may explain why its effects don’t appear as robust or enduring as those of IV ketamine.

4. How Does Ketamine’s Rapid Relief Timeline Improve Treatment Success Rates?

IV ketamine works substantially faster and requires fewer sessions to achieve significant relief compared to Spravato, dramatically improving treatment compliance. This rapid-acting profile represents a fundamental advantage in depression treatment.

Patients typically experience meaningful improvement after just 1-2 IV ketamine infusions, whereas Spravato often requires multiple sessions before noticeable benefits emerge. This faster therapeutic onset not only provides earlier symptom relief but also reinforces patient motivation to complete the treatment protocol.

Supporting this advantage, IV ketamine’s efficiency extends to the overall treatment time commitment. The average IV ketamine session takes approximately 1 hour and 43 minutes versus Spravato’s 2 hours and 15 minutes. Over the course of treatments this cumulative effect is substantial: approximately 13.5 total clinic hours for IV ketamine versus 31.5 hours for Spravato—a difference of 18 hours. For patients struggling with depression, who already face challenges with energy and motivation, this reduced time burden removes a significant barrier to treatment completion, further enhancing the likelihood of achieving remission.

What Do Ketamine’s Advantages Mean for Your Depression Treatment Success?

The combined advantages of complete bioavailability, personalized dosing, full molecular composition, and faster relief with fewer sessions create a treatment that delivers more consistent, predictable, and potent antidepressant effects. These factors work synergistically to enhance both effectiveness and compliance, explaining why systematic reviews consistently show IV ketamine producing stronger results.

The time efficiency of IV ketamine—requiring approximately 18 fewer clinic hours over a complete treatment protocol—addresses a critical barrier for depression patients who already struggle with energy and motivation. This reduced burden, coupled with more rapid symptom improvement, significantly increases the likelihood that patients will complete the full treatment course necessary for remission.

However, treatment decisions should balance these effectiveness considerations with practical realities. Despite IV ketamine’s therapeutic superiority, Spravato holds a significant advantage in accessibility since insurance companies are more likely to cover it. For many patients, a partially covered treatment that works moderately well may be preferable to an out-of-pocket treatment with higher effectiveness.

The scientific evidence clearly indicates IV ketamine’s advantages, but the best choice ultimately depends on each patient’s unique circumstances, including financial resources, insurance coverage, time constraints, and the severity of their depression.

What Do 33 Systematic Reviews Reveal About Ketamine’s Effectiveness for Depression?

(Every systematic review published between 2020 – 2024)

The table below is the foundation for everything on this page. It gathers every systematic review and meta-analysis on ketamine therapy published between 2020 and 2024—33 in total. It took months of research to uncover them, verify their scope, and extract key findings.

We built our remission estimates from this full body of evidence—not from cherry-picked studies or one-off success stories. IV, injection, oral, and esketamine nasal spray methods are all represented. So when we say “up to 72%” remission is possible, this is the deep well of science behind it.

Why Cherry-Picked Ketamine Studies Can Mislead Patients About Real Depression Outcomes

I don’t rely on individual studies to make my case, even though plenty exist that might seem to prove my point. For instance, one study on IV ketamine reported a 79% remission rate after a nine-month follow-up.

Another study on Spravato (the esketamine nasal spray) showed a remission rate of up to 64% after twelve months. If I wanted to dazzle you, I could stop there. But that would be a lie of omission.

How Selective Research Reporting Distorts the Truth About Ketamine Therapy Results

Because here’s the problem: leaning on individual studies is a dangerous game. It means cherry-picking—intentionally or not—the studies that say what you want them to say while conveniently ignoring the ones that don’t. 

Yes, I could cite that 64% remission figure for Spravato, but there are plenty of other studies showing far lower remission rates, some barely above placebo. Why don’t I showcase those? 

And as for that glowing 79% IV ketamine figure? It came from a single study, with just 56 people. 

Holding up isolated studies as proof isn’t just sloppy—it’s reckless. You are distorting reality when you pretend one or two studies speak for an entire field of research. Science doesn’t move forward because of one dramatic study. It moves forward when we step back, gather every piece of evidence, and weigh them as a whole—including the ones that don’t say what we wish they did. 

Why Do Systematic Reviews Provide the Most Reliable Evidence for Ketamine’s Depression Benefits?

That’s why the only numbers you’ll ever see me use come from systematic reviews and meta-analyses–because they keep us from getting fooled by outliers or one-off flukes. They tell us what’s real across studies, across patients, and across outcomes—not just what happened in a tiny group of 56 people or in one study that happened to get unusually positive results.

Systematic reviews and meta-analyses gather all the relevant research that meets clear, published standards and weigh the quality and consistency of that evidence, so we know how strong—or weak—the case really is. If you want to understand what’s actually happening in the real world—not just in the best-case scenario—systematic reviews and meta-analyses are the only way to get there.

Remission tiptoed in when I wasn’t looking.

Scales and checklists are helpful, but the real test of remission is how you actually feel. Long before my psychiatrist or the Beck scores pronounced me in remission, I knew I was getting better because my life started to change. The awful feelings that once controlled me were waning, and slowly I stopped trying to drown them in pills or alcohol.

I’ll never forget the moment I recognized real progress. I was in the ketamine clinic, and I caught my reflection in the mirror. At first, I didn’t recognize myself. Normally, I walked in looking like a wreck: unshowered, unshaven, dressed in whatever was closest to the bed. But that day? I was clean-shaven, freshly showered, wearing clothes that actually fit me. I’d even woken up early—early!—to work out before my session.

It wasn’t something I planned. I didn’t wake up and decide to put my life together that day. It just happened. That’s the thing about remission—it sneaks up on you. There’s no big “TA-DAH!” moment. One day, you look in the mirror, and you see someone you almost forgot existed.

How Noticing Old Habits Keeps Me in Remission

​​Staying in remission means catching yourself before old habits pull you back into depression. For me, one big red flag is cutting off contact with family and friends—letting calls go to voicemail and ignoring texts. That was always one of the first things I did when depression hit hard.

Now, when I catch myself slipping into that pattern, I know exactly what’s happening and where it leads—and I act before it takes hold. Sometimes it’s sheer willpower, picking up the phone and calling or texting back. Other times, I stop and think about why I’m starting to isolate and face it head-on. And if I need extra help, I don’t hesitate to go back to my therapist. It’s about stopping the spiral before it starts.

Staying in remission is also about creating the kind of life that keeps depression from finding a way back in. I prioritize sleep like it’s medicine, stick to a routine that includes exercise, and make time for things that genuinely bring me joy, even on busy days. 

Man, I’m making myself sound like some self-help guru who’s nailed life, like I’ve got everything figured out and my days end with birds singing me to sleep. It ain’t true. I struggle but I don’t see my struggle as all that different from what anyone else deals with. People without depression have to work to keep their life on track, too. The only difference is I know what happens if I let things slide, so I try to stay on top of it. Not perfectly, not always gracefully, but enough to keep moving forward.