Ketamine vs Esketamine (Spravato) for Depression: What Is the Difference?

If you have been reading about ketamine for depression, you have probably run into two names that seem to mean the same thing: ketamine and esketamine, the latter usually attached to the brand Spravato. They sound interchangeable, and clinics sometimes talk about them as if they are. They are not. They are close relatives that share a mechanism, but they differ in almost every practical way that matters to you: how you get them, what rules surround them, what the evidence says, and what you will pay. If you are trying to decide whether either one is right for you, the differences are the whole point. Here is a clear, honest map.

The short version: same molecule, different products

Ketamine is a single molecule that comes in two mirror-image halves, called enantiomers. Regular ketamine, the kind used in operating rooms and in most infusion clinics, is a mix of both halves. Esketamine is just one of those halves -- the S-enantiomer -- purified and turned into a nasal spray. Because it binds the target receptor more tightly, effective doses are smaller.

That target is the NMDA receptor, part of the brain's glutamate signaling system. Blocking it sets off a downstream cascade that appears to rebuild and strengthen neural connections, which is thought to be why both forms can lift mood within hours to days rather than the weeks that older antidepressants often take (https://pubmed.ncbi.nlm.nih.gov/29532791/). So the biology overlaps a great deal. The products built around that biology do not.

The single most important difference: esketamine, sold as Spravato, is FDA-approved for depression. IV and generic ketamine are not. Spravato is approved for treatment-resistant depression and for major depressive disorder with acute suicidal ideation or behavior (https://www.jnj.com/media-center/press-releases/spravato-esketamine-approved-in-the-u-s-as-the-first-and-only-monotherapy-for-adults-with-treatment-resistant-depression). Ketamine is used off-label, meaning a clinician prescribes it for depression even though the FDA approved the drug for other purposes.

How esketamine (Spravato) is given

Spravato is a nasal spray you use yourself, but only inside a certified clinic and under direct supervision. You spray it, then you sit and are monitored. Doses are standardized (commonly 56 mg or 84 mg per session), and the early phase of treatment is typically twice a week, tapering to weekly and then every other week as you stabilize. It is often paired with an oral antidepressant, though it is now also approved to be used on its own.

Absorption through the nose is gradual and incomplete, with roughly half the dose reaching the bloodstream, so the effects tend to build more slowly and feel milder at the start than an infusion does (https://pmc.ncbi.nlm.nih.gov/articles/PMC12615959/). You do not handle the drug at home. You do not keep a supply. Every dose happens in the clinic.

How IV or generic ketamine is given

Racemic ketamine for depression is usually delivered as an intravenous infusion, dripped in over about 40 minutes at a low, sub-anesthetic dose (often around 0.5 mg/kg). Because it goes straight into the bloodstream, the effect comes on quickly and feels more pronounced. A typical starting course is a series of infusions -- frequently six over two to three weeks -- followed by maintenance sessions spaced out based on response.

Since ketamine is off-label here, protocols are far less standardized than Spravato. Dose, frequency, and monitoring vary from clinic to clinic. That flexibility can be a strength in experienced hands, but it also means quality and safety practices are uneven across providers. It is worth asking any clinic directly how they dose, who supervises, and how they monitor you afterward.

The REMS rules, and why they exist

Spravato carries a boxed warning and is only available through a federal safety system called a REMS, short for Risk Evaluation and Mitigation Strategy. In plain terms, the FDA decided this drug needs guardrails, so it wrote them into law.

Under the Spravato REMS, every dose is given in a certified healthcare setting, and a provider must monitor you for at least two hours afterward, watching for sedation, dissociation, and changes in blood pressure and breathing (https://spravatorems.com/pdfs/REMSProgramOverview). Sedation usually peaks in the first 30 to 60 minutes and dissociation in the first 30, so most effects have settled by the two-hour mark. You cannot drive or operate machinery for the rest of the day, and you should not do either until after a full night of sleep. The drug is never sent home with you.

IV ketamine has no equivalent national program, precisely because it is off-label. Good infusion clinics follow similar safety practices out of clinical judgment, not legal requirement. That distinction is one reason we take clinic selection seriously.

What the evidence says about who they help

Both forms are studied in the same population: people whose depression has not responded to standard treatment. Spravato has the more formal evidence base because approval required it, including trials in people with active suicidal thinking, where it reduced depressive symptoms faster than placebo added to standard care (https://academic.oup.com/ijnp/article/24/1/22/5899217).

Head-to-head comparisons are where people most want clarity, and the honest answer is that the data is still thin. A 2025 systematic review pooling eight studies found broadly comparable response and remission rates, with a hint that IV ketamine may act somewhat faster, but no statistically significant winner and mostly observational studies behind it (https://pmc.ncbi.nlm.nih.gov/articles/PMC12615959/). A separate 2025 clinic-based comparison did find a larger average symptom drop with IV ketamine (about 49 percent versus 40 percent), and slightly earlier improvement (https://www.massgeneralbrigham.org/en/about/newsroom/press-releases/ketamine-esketamine-comparison-study). Those are real signals, but they are not the large randomized trials that would settle the question. For now, the fair summary is that both help many people with treatment-resistant depression, and neither is clearly superior for everyone. Broader reviews of ketamine reach the same measured conclusion: promising, rapid, and still being refined (https://pubmed.ncbi.nlm.nih.gov/31695324/).

Cost and insurance: the real difference

This is where the FDA approval stops being abstract. Because Spravato is approved, insurers are more likely to cover it, usually after a prior authorization and documentation that other antidepressants have failed. That paperwork is a hurdle, but it is a path.

IV and generic ketamine for depression are off-label, so most insurance plans will not pay for the infusions themselves, and patients often cover the full cost out of pocket. The per-session price of an infusion can look lower than a Spravato session, but coverage, not sticker price, is what usually decides affordability over a full course. We help patients think this through honestly rather than steering them toward whatever a given clinic happens to sell.

Safety, dissociation, and what to expect

Both treatments can cause dissociation, a temporary feeling of being detached from your body or surroundings, along with drowsiness, nausea, a short-lived rise in blood pressure, and a floaty or dreamlike state. For most properly screened patients in a supervised setting, these effects are manageable and fade within a couple of hours. Longer-term concerns, including bladder problems and the potential for misuse, are tied mainly to high or unsupervised dosing, which is exactly what clinical protocols are built to avoid.

Screening matters. Uncontrolled high blood pressure, certain heart conditions, active substance misuse, and some psychiatric histories change the risk calculation. This is not a treatment to start casually, and it is not something to attempt at home.

These are for treatment-resistant depression, under supervision

Neither ketamine nor esketamine is a first step. They are for depression that has not responded to standard treatment, usually meaning at least two adequate antidepressant trials have failed, or for depression with acute suicidal thinking. They belong in a supervised clinical setting with real monitoring, not in a mailbox or a wellness subscription. Used that way, for the right person, they can help when other options have not.

If you have been fighting a depression that has not lifted despite doing the right things, you deserve a careful evaluation and a straight answer about whether a ketamine-based option fits, and which one. At NoMi Beach Health, Dr. Jezwah Harris reviews your history, your prior treatments, and your safety profile, then tells you plainly what we recommend and what should come first. You can learn more or book a new-patient visit through our mental health services page, or read more of our patient guides on the blog. If you would rather talk it through, call us at (786) 744-5152.