Sublingual vs Nasal Ketamine: Which Route Works Best?

You've decided ketamine therapy might be worth trying, maybe after a long stretch of treatments that didn't deliver. Now you're stuck on a different question: which form do you actually choose? Lozenges that dissolve under your tongue, or a nasal spray?

It's a confusing choice, partly because "nasal ketamine" can mean two different things, and the two routes aren't backed by the same kind of evidence.

The short answer: If you have insurance and qualify for Spravato for treatment-resistant depression (TRD), it's usually the stronger evidence-based choice. If cost, privacy, and at-home access matter most, sublingual ketamine is often the more accessible option. FDA status, treatment setting, evidence quality, cost, monitoring, and your own situation all shape which one fits.

What Is Sublingual Ketamine?

Sublingual ketamine is racemic ketamine, a 50/50 mix of two mirror-image versions of the molecule, formulated as a slow-dissolving lozenge, troche, or liquid. In plain terms, it's ketamine made to absorb through your mouth instead of through intravenous (IV) treatment or nasal spray.

You hold it under your tongue or against your cheek while it absorbs through the mouth's tissues, rather than chewing or swallowing it. Your clinician sets the dose based on your medical history, treatment plan, and response.

Sublingual ketamine isn't FDA-approved for depression or anxiety. A licensed pharmacy custom-mixes it, and its use for mental health is off-label. Because it's compounded, there's no FDA-approved dosing standard. It can be used in at-home ketamine therapy and is often prescribed through telehealth.

What Is Nasal Ketamine?

The term "nasal ketamine" can mean two very different products:

1. Spravato

The first is Spravato (esketamine), an FDA-approved nasal spray containing only the S-version of the molecule, not the full racemic mix. The FDA approved it in 2019 for treatment-resistant depression and, in January 2025, as a standalone treatment usable without a daily oral antidepressant, an indication formalized in the agency's 2025 approval letter.

More than 140,000 people worldwide have received it. It can only be taken inside a certified clinic under supervision, never at home, and a federal safety program requires monitoring for at least two hours after each dose.

It also carries the FDA's most serious warning level for sedation, dissociation, and misuse.

2. Compounded racemic ketamine nasal spray

The second is compounded racemic ketamine nasal spray, which is not FDA-approved and which the FDA has flagged for adverse events tied to at-home use. The comparison below treats "nasal" mostly as Spravato, since that's the regulated option.

One caveat: no head-to-head study has directly compared sublingual against esketamine nasal spray, so the comparisons pull from separate bodies of research and the answer isn't as clean as anyone would like.

How Each Route Absorbs and Works

Bioavailability is the amount of medication your body actually absorbs, and higher bioavailability means more of the drug reaches your brain at a given dose. It's one reason two routes can feel different even with closely related medications, and it works alongside how ketamine works in the brain once it arrives.

1. Sublingual ketamine. Sublingual absorbs through the lining of your mouth for roughly 30% bioavailability, well above the 10 to 20% of a swallowed pill. That number is also relatively steady: technique matters, and holding the dose under your tongue for the full dissolve time, rather than swallowing early, is what protects that absorption. Most people notice effects within 15 to 30 minutes, peaking around 45.
2. Nasal esketamine (Spravato). Nasal delivery gets more medication into your bloodstream, in the 25 to 50% range; a bit higher on average than sublingual. But that range is wide, and congestion, inflammation, or your nasal anatomy on any given day can swing it significantly. Onset is faster, within 5 to 15 minutes. If you're in an acute crisis, that speed, paired with a supervised clinic setting, is a real practical advantage.
3. IV ketamine (for context). IV sits above both routes on absorption and is often treated as the clinical reference point. Our guide on at-home vs infusion covers that separate tradeoff.

The ranges overlap more than "higher" and "lower" suggest, so absorption alone can't settle the choice. Where the routes really diverge is in consistency, onset speed, and what the setting around them looks like — which is where the decision starts to take shape.

What the Evidence Actually Shows

Spravato has FDA-level randomized controlled trials (RCTs) behind it. Sublingual ketamine has observational studies, retrospective chart reviews, and case reports. A Canadian clinical guideline rates it at level 4 evidence, the lowest tier, and recommends it be prescribed only by specialists with ketamine expertise.

Spravato trials show several findings. In the TRANSFORM-2 trial, esketamine plus a new oral antidepressant beat placebo, a relapse-prevention study found people who stayed on it were roughly half as likely to relapse, and in the monotherapy study behind the 2025 approval, 22.5% reached remission at week four versus 7.6% on placebo. Not every trial was positive, though: the TRANSFORM-1 trial found no significant difference at one dose level.

Sublingual evidence is encouraging but softer. A prospective telehealth study reported a 60% response rate after four weeks, and another found nearly half of people with moderate-to-severe depression improved, rising to 60% among those who finished a full course of 12 treatments. These are real signals, but observational studies can't rule out selection bias the way a controlled trial can.

The picture is thinner for other conditions. Evidence for PTSD mostly comes from IV studies, and for suicidal thoughts, most evidence comes from IV ketamine and intranasal esketamine. No randomized trials have tested sublingual ketamine specifically for suicidal ideation, a meaningful gap if crisis relief is your priority.

What a Session Can Look Like

A sublingual session can happen in a private office or at home over telehealth. You'd settle in with an eye mask and calming music, often after a short intention-setting conversation. The lozenge dissolves over 15 to 20 minutes, then the experience runs roughly 45 to 60 minutes, often felt as a meditative trance or a mild floating sensation.

A Spravato session looks different. You self-administer the spray in a certified clinic, and the structure centers on safety monitoring. Dissociation peaks around 40 minutes and grogginess can linger. The FDA notes that 61 to 84% of people experience perceptual changes like distortion of time and space.

You can't drive yourself home, and you can't drive until you've had a full night's sleep.

Cost and Insurance

For many people, this is the deciding factor. Spravato's FDA approval can make insurance coverage easier to pursue than compounded sublingual ketamine, though prior authorization and plan details still matter.

With commercial insurance, a savings program can drop the medication cost to as low as $10 per treatment for people who qualify, though clinic and observation fees may be separate.

Without insurance, Spravato gets expensive fast, since the medication and the required clinic visits may both come out of pocket. Sublingual is harder to predict on coverage because it's off-label and compounded, but out of pocket it's often more affordable than uninsured Spravato, especially through telehealth.

Neither route is automatically the budget choice until insurance is in the picture.

Side Effects and Safety

Both routes share a core set of side effects, because the same drug, or a close chemical cousin, reaches your brain, and the broader question of whether ketamine is safe comes down to setting as much as chemistry: dissociation, a floating or detached feeling, dizziness, nausea, mild sedation, and a temporary rise in blood pressure.

These usually appear within 10 to 40 minutes and fade within 60 to 90 minutes. For Spravato specifically, controlled studies put dizziness around 31% and dissociation at 31.4% versus 12.9% on placebo.

Safety reviews haven't found meaningfully different side-effect profiles between routes. What separates them most clearly is supervision. With Spravato, a clinician is present the whole time; with at-home sublingual, no one is physically there if something goes wrong.

The FDA has warned that home use removes the safety net of in-person dose adjustment, and a Cleveland Clinic clinician has urged caution around addiction and overdose risks. The quality of the clinical oversight matters as much as the medication.

Ketamine therapy isn't right for everyone. If you have poorly controlled high blood pressure, certain heart or vascular conditions, a history of psychosis, or you're pregnant, a qualified clinician should be direct about those risks and help you consider a safer path.

Screening matters. Long-term use of any route also carries risks worth knowing, including potential bladder and cognitive effects that appear to reverse when use stops.

Why Preparation and Integration Matter

What happens around the medication can shape how much it helps. The medication opens a door; therapy helps you walk through it. Ketamine briefly increases neuroplasticity, so your brain becomes more able to form new patterns. That window is most useful when you work with it on purpose.

Preparation beforehand and integration afterward give you a way to process what comes up and make it last. This is where the routes diverge: a sublingual program is more often built around that psychological work, while a Spravato visit centers on safety monitoring. Both designs are valid; they serve different needs.

Comparing the Two Routes

The sections above cover each dimension on its own. Here's how they line up side by side.

Which Route Might Fit You

There's no universal winner; the right route depends on which constraint is doing the most work in your decision. Start with what matters most to you, and the choice usually narrows quickly.

• If you have insurance that covers Spravato: nasal esketamine is often the strongest pick, since coverage can make the FDA-approved, better-studied option the affordable one too.
• If cost is the barrier and you're uninsured: sublingual is usually the more affordable path, especially through telehealth, with no clinic fees stacking up.
• If you're in acute crisis or have severe depression: a supervised route such as nasal or IV carries the stronger evidence for fast, monitored relief.
• If at-home access or privacy is the priority: sublingual fits a schedule, a rural location, or a need for discretion in ways a clinic can't.
• If you want therapy woven into treatment: sublingual is more often built around ketamine-assisted psychotherapy, while Spravato visits center on monitoring.
• If you have cardiovascular risks or a complex medical history: the supervised clinic setting is a real safety advantage worth the added logistics.

The tradeoffs cut both ways. Nasal means twice-weekly induction visits, travel, and a ride home, but stronger evidence and clinic oversight. Sublingual means weaker evidence and no required in-person monitoring, but far more flexibility.

Whichever way you lean, the safest decision is one a clinician makes with you, weighing your full medical history.

How Innerwell's At-Home Ketamine Therapy Works

If you've decided the at-home, therapy-integrated route fits your situation, here's what that looks like in practice. Innerwell offers at-home sublingual ketamine therapy with clinical support built around it. This isn't ketamine dropped off at your door with minimal supervision; licensed psychiatric providers and Master's and Doctoral level licensed therapists are involved at every step.

The process:

1. Evaluation: A licensed psychiatric provider reviews your medical history, current medications, past treatment responses, and goals to see whether ketamine therapy is appropriate and safe for you.
2. Delivery: If you're a fit, sublingual tablets are sent to your home through licensed pharmacy shipping, with no IV clinic visits required.
3. Preparation and integration: You meet with a Master's or Doctoral level licensed therapist before treatment to set intentions and afterward to process what came up.
4. Ongoing monitoring: Innerwell's clinical team tracks your progress and adjusts the plan as needed.

Pricing: With Innerwell's insurance partnerships, sessions cost approximately $54–$75. Self-pay sessions cost approximately $83–$125. Treatment is typically HSA/FSA eligible.

Program outcomes: Innerwell members have seen a 69% reduction in depression symptoms and a 60% reduction in anxiety symptoms after ten weeks. Roughly 87% experience improvement within four weeks, and the program holds a 4.7 out of 5 average rating.

Take our free assessment to see if ketamine therapy might be right for you.

Frequently Asked Questions

How many sessions will I need, and for how long?

The two routes differ here. Spravato follows a fixed schedule: twice a week for the first four weeks, then weekly, then every one to two weeks for as long as you keep responding, all in a clinic. Sublingual programs usually start with a shorter initial series, often six to eight sessions over a few weeks, then taper to maintenance based on how you respond. Your clinician sets the dose and pacing to fit you, so plan for an ongoing commitment rather than a one-time fix.

Is sublingual ketamine FDA-approved?

No. Sublingual ketamine is used off-label through compounding pharmacies and isn't FDA-approved for any psychiatric condition. The only FDA-approved ketamine-related treatment for depression is Spravato, the esketamine nasal spray, which is why it comes with strict monitoring rules and broader insurance coverage.

Can I switch from one to the other later?

Yes. Neither choice is permanent. Some people start with at-home sublingual for convenience and move to Spravato if they need the stronger evidence base or a more structured clinical setting; others go the opposite direction once their symptoms stabilize and they want more flexibility. Because the medications are closely related, a clinician can adjust your route, dose, and schedule over time based on how you respond rather than locking you into one path from the start.