The Guide to Oral and Sublingual Ketamine Dosing for Depression: Evidence From 26 Clinical Studies

By Michael Alvear, Health Author & Independent Researcher

My research is published on these scholarly platforms:

Last Updated: May 23, 2026

70mg for a 154-pound adult — about 0.45mg per pound — is the simplest weight-based oral ketamine reference point in our analysis.

That number comes from 1mg per kilogram of body weight, a dose used in key oral ketamine studies. Translated into U.S. terms, 1mg per kilogram equals about 0.45mg per pound. For a 154-pound adult, that lands at about 70mg.

150mg per treatment is the simplest fixed-dose oral ketamine reference point.

That number works differently. It is not scaled to the body. A 110-pound person and a 330-pound person can both be handed 150mg, but they are not getting the same dose in any meaningful body-weight sense. The label says the same thing. The body receives something very different.

Quick oral dosing facts

These numbers come from the oral ketamine studies inside our 26-study analysis. They are not instructions for what to take. They are reference points for understanding the number you were given.

• Most useful weight-based dose: 0.45mg per pound
  That equals 70mg for a 154-pound adult and comes from the 1mg-per-kilogram dose used in key oral ketamine studies.
• Clearest fixed oral session dose: 150mg per treatment
  This is the strongest simple fixed-dose number in repeated oral ketamine treatment studies.
• Low-end oral dose: 50mg/day
  This shows up as a low daily dose, a starting dose, or a dose used for lower-weight patients.
• Upper-end structured oral dose: 1.36mg per pound
  That equals 210mg for a 154-pound adult and comes from 3mg per kilogram, an upper-end research dose.
• Higher lower-certainty oral dose: 300mg per occasion
  This appears in a retrospective case series. It is part of the record, but it is not as strong as the better-structured studies.

0.45mg per pound — about 70mg for a 154-pound adult — is the first number to understand.

150mg per treatment is the second number to understand.

This is the fixed-dose comparison point. Instead of calculating the dose from body size, a fixed-dose protocol gives the same amount to everyone. That can be convenient. It is also where confusion starts.

So the real patient question is not just:

“How much oral ketamine should I take?”

The better question is:

“Is my dose based on my body weight, or am I getting a fixed amount?”

That question will tell you far more than the milligram number by itself.

0.45mg per pound is the key body-weight number.

This is where fixed dosing can get misleading.

150mg sounds like one dose. It is not. Not really.

For a 110-pound adult, 150mg equals about 3mg per kilogram — the upper end of the structured oral research range.

For a 154-pound adult, 150mg equals about 2.14mg per kilogram — solidly inside the research range.

For a 198-pound adult, 150mg equals about 1.67mg per kilogram — lower in the research range.

For a 287-pound adult, 150mg equals about 1.15mg per kilogram — close to the bottom.

For a 331-pound adult, 150mg equals 1mg per kilogram — the minimum weight-based dose used in key positive oral ketamine research. The white paper’s fixed-dose table lays out this drop clearly: the same 150mg prescription moves from 3mg/kg at 110 pounds to 1mg/kg at 331 pounds.

Same bottle. Same 150mg. Five very different body-weight doses.

That is the trap in fixed dosing. It looks simple because the number does not move. But the dose moves inside the body.

It is like putting the same amount of gas in a motorcycle, a sedan, and a moving truck. The number at the pump is the same. The range you get from it is not.

That does not prove a heavier patient will fail at 150mg. It does not prove a lighter patient is unsafe at 150mg. It proves something narrower and still important:

Fixed dosing gives lighter patients more ketamine per pound and heavier patients less ketamine per pound.

That is not an opinion. It is arithmetic.

This is why the question should never stop at:

“How many milligrams am I taking?”

The better question is:

“How many milligrams am I taking for my weight?”

That is the difference between reading the label and understanding the dose.

150mg looks equal. It is not equal.

Fixed dosing gives every patient the same number of milligrams. That feels clean. It feels standardized. It is easy for clinics to explain and easy for telehealth platforms to scale.

But simplicity is not the same thing as precision.

The white paper makes the key point: fixed-dose prescribing is not a neutral administrative shortcut. It changes who gets more drug per pound and who gets less. Lighter patients can land near the top of the research range. Heavier patients can land near the bottom.

That does not mean fixed dosing is always wrong. It means fixed dosing should not be treated as if body weight disappeared.

For patients, this matters because treatment-resistant depression often does not arrive in an “average” body. Many people seeking ketamine have already spent years on antidepressants or augmentation medications that can cause weight gain. The white paper argues that this may put some of the very patients most likely to seek oral ketamine into the group most disadvantaged by one-size-fits-all dosing.

That is not a reason to change your dose on your own.

It is a reason to ask a better question:

“Has my weight been considered in this dose?”

50mg is a low-end oral ketamine dose in our 26-study analysis.

This question matters because 50mg is the kind of number that can make patients nervous in both directions.

Some people see 50mg and think:

“That seems tiny. Am I being underdosed?”

Others see any ketamine dose and think:

“Is this too much?”

In the oral ketamine studies we reviewed, 50mg was not the main reference point. It showed up in lower-dose roles:

• •

  50mg/day was used as a fixed daily dose in one controlled study.

• •

  50mg was used as a starting dose in one retrospective oral ketamine case series.

• •

  50mg was used as a lower starting dose for patients under about 88 pounds in one later study.

So yes: 50mg is low compared with the strongest oral dose reference points in this analysis.

But low does not mean useless. Low does not mean wrong. Low does not mean safe. It means the number needs context.

50mg once a week is very different from 50mg every day.
50mg as a starting dose is very different from 50mg as the final dose.
50mg for a 95-pound patient is very different from 50mg for a 240-pound patient.

A dose number without schedule and body weight is like a street address without the city. It looks specific, but you still do not know where you are.

150mg per treatment is the clearest fixed-dose oral ketamine number in our analysis.

This is the number that deserves attention if your prescription is not based on body weight. It is simple. It is recognizable. It shows up in fixed-dose oral treatment contexts.

But 150mg is not one thing.

It can mean:

• •

  150mg in one treatment session

• •

  150mg total across a full day

• •

  150mg as a starting dose before possible increases

• •

  150mg as a fixed dose regardless of weight

Those are different clinical designs.

150mg in one session is one treatment event.
150mg spread across a day is a divided daily schedule.
150mg as a starting dose may be part of a titration plan.
150mg in a 110-pound person is a much larger body-weight dose than 150mg in a 331-pound person.

That is why “Is 150mg normal?” needs a sharper answer:

150mg is the clearest fixed-dose oral ketamine reference point in our analysis, but it is only meaningful if you know the schedule, your weight, the formulation, and whether the dose is meant to change.

The number is the headline. The schedule and body weight are the plot.

210mg for a 154-pound adult — about 1.36mg per pound — is the cleanest upper-end structured oral dose in our analysis.

That number comes from 3mg per kilogram of body weight, an upper-end dose used in structured oral ketamine research.

It is not a safety ceiling.
It is not a target.
It is not a green light to increase your dose.

It is simply the upper edge of the better-organized oral dosing map.

Higher numbers exist, but they do not all deserve the same confidence.

The fixed-dose math matters here too.

300mg is not the same dose for every body:

Same 300mg. Three very different positions on the map.

That is why “How high is too high?” cannot be answered by milligrams alone. A number can appear in the literature without becoming a good guide. A number can also look high until body weight puts it into context.

Think of the research record like a road map. The well-marked roads matter more than the faint trail at the edge. The 210mg reference point is on the clearer road. The higher numbers are worth knowing about, but they should not be treated as the route.

This chart shows the oral ketamine rows from our 26-study analysis. It is here so you can see where the numbers came from.

The chart does not produce one universal oral ketamine dose. That is the point.

But it does show a pattern strong enough to help patients get oriented:

Body-weight dosing appears repeatedly. Fixed 150mg oral sessions appear repeatedly. Several-times-weekly or every-few-days dosing appears repeatedly.

That is why this analysis is useful. It does not pretend the field has a standard it does not have. It gives you the closest practical substitute: the dose and schedule choices researchers kept returning to when they had to design actual studies.

70mg in an oral liquid is not the same thing as 70mg in an extended-release tablet.

The milligram number tells you how much ketamine is in the product. It does not tell you how fast the ketamine is released or how your body receives it.

That difference matters.

An oral liquid or immediate-release capsule is built to make the dose available sooner after swallowing. An extended-release or prolonged-release tablet is built to release ketamine more slowly over time.

Same label number. Different delivery.

Think of it this way:

Immediate-release oral ketamine is more like pouring water from a glass. Extended-release ketamine is more like a slow-drip faucet.

Both can contain the same amount of water. But your body does not receive them at the same speed.

That is why extended-release ketamine studies cannot be used casually to judge standard immediate-release oral ketamine, compounded capsules, liquids, or sublingual products. The white paper makes this point with the BEDROC extended-release trial: its fixed doses were used in a formulation engineered to change the release curve, so they do not validate fixed dosing for standard immediate-release oral or sublingual ketamine.

The oral ketamine studies in our 26-study analysis included several forms:

• •

  Oral liquid solution

• •

  Oral capsules

• •

  Oral tablets

• •

  Extended-release or prolonged-release tablets

• •

  Oral esketamine, which is not the same as racemic ketamine

The main oral-dose numbers in this section focus on standard swallowed oral racemic ketamine — mostly liquid, capsule, or immediate oral dosing patterns.

Extended-release and prolonged-release tablets belong in a separate bucket because they change the delivery curve. Oral esketamine belongs in a separate bucket because it is not the same drug mixture as racemic ketamine.

So before comparing your dose to anyone else’s, ask four questions:

• ?

  How many milligrams is the dose?

• ?

  Is it based on my weight?

• ?

  How often am I taking it?

• ?

  What form is it — liquid, capsule, tablet, or extended-release tablet?

Without those answers, the milligram number is not the whole dose. It is only the number printed on the package.

There is one more thing those charts do not show: the frequency those platforms use. Wondermed, Nue Life, and Mindbloom all dose once weekly or less. Zero of the 26 clinical studies in this analysis used a once-weekly protocol. Every positive controlled trial used two to three sessions per week. The dose numbers in the sublingual record come largely from platforms whose dosing schedule has never appeared in a controlled trial.

Why Sublingual, Oral, and IV Ketamine Milligrams Are Not Comparable

Those numbers help explain why many patients see sublingual ketamine doses that look much higher than swallowed oral ketamine doses.

But the delivery system is different.

300mg swallowed, 300mg held under the tongue, and 300mg given by IV do not mean the same thing. The number is the same. The route is not.

When ketamine is swallowed, the liver destroys roughly 80 to 84 percent of it before it reaches the bloodstream — leaving only about 16 to 17 percent as active exposure. Hold a lozenge under the tongue instead of swallowing it, and that figure roughly doubles to about 30 percent, because some of the drug absorbs directly through the mouth’s blood vessels and bypasses the liver entirely. That is why 150mg swallowed delivers roughly the same systemic exposure as 25mg by IV. Not four times more. About the same.

That is the first rule of sublingual ketamine dosing: do not compare milligrams across routes as if the body receives them the same way.

How Much Sublingual Ketamine Should I Take for Depression?

There is no standard sublingual ketamine dose for depression.

The best research-record answer is narrower:

Real-world sublingual reports commonly cluster around 150–600mg per session, depending on the product, program, schedule, and study design.

That is not one protocol. It is a map of what has been reported.

A 150mg sublingual lozenge, a 300mg RDT, and a 600mg rapidly dissolving tablet are not simply “low, medium, and high” versions of the same thing. They may come from different programs, different instructions, different schedules, and different evidence quality.

A dose number without the form and schedule is like a street address without the city. It looks specific, but you still do not know where you are.

So the better patient question is not only:

“How much sublingual ketamine should I take?”

The better question is:

“What form am I taking, how often am I taking it, and how does that number compare with the sublingual ketamine dosing record?”

300mg is the most recognizable sublingual ketamine dose in the real-world reports we reviewed.

That does not mean 300mg is the right dose for you. It means 300mg shows up often enough in sublingual ketamine dosing reports that it deserves to be treated as a serious reference point, not as a random internet number.

That reference point matters more than it might seem. A sentinel surveillance study of 75 patient reports found that real-world at-home doses span a 120-fold range — from 10mg to 1,200mg per session. Most of those patients had no way of knowing whether their dose bore any relationship to what researchers had actually studied. That is exactly what this article documents.

The sublingual ketamine dosage record is messier than the swallowed oral ketamine record. The clearest oral studies include more controlled and structured protocols. The sublingual record leans more heavily on real-world telehealth reports, open-label studies, retrospective data, and records where dosing was individualized or incompletely reported. The randomized controlled trials underlying clinical confidence in these doses are almost universally underpowered — most enrolled fewer than 50 participants. No dose-finding trial for sublingual ketamine has ever been conducted — the specific type of study designed to identify the minimum effective dose, the optimal dose, and the upper safety boundary. The numbers in this article come from trials that picked a dose and tested it. Not from research that methodically mapped the dose landscape.

Still, the numbers are useful.

In the sublingual, RDT, lozenge, and troche-related reports in our 26-study analysis, the main dose numbers were:

• •

  150–200mg per session in one real-world sublingual lozenge program

• •

  50–400mg as the broader range in that same lozenge report

• •

  300mg as an initial sublingual RDT dose in one large at-home telehealth report

• •

  300–450mg as an initial or adjusted RDT/lozenge range in real-world reports

• •

  300–600mg as an initial RDT/lozenge range in one large retrospective platform report

Those numbers also reflect one slice of the prescribing landscape. Most of the sublingual reports in this analysis come from telehealth platforms — Mindbloom, Nue Life, Wondermed. A second, frequently overlooked channel is local psychiatrists and physicians prescribing through compound pharmacies. Compounding pharmacy data shows most such prescriptions run lower: 50–300mg, up to three times weekly for one to three months — a frequency that sits closer to what the research evidence actually tested than the once-weekly telehealth standard. A third channel — therapist-assisted sessions with compounded ketamine in a supervised clinical setting — exists but contributes little to the published dosing record. The charts in this article skew toward what telehealth platforms reported. Keep that in mind when comparing your dose to the numbers on this page.

300mg is not an outlier in the sublingual ketamine reports we reviewed.

In one large real-world telehealth report, 300mg was used as an initial sublingual RDT dose. Some patients stayed at 300mg, while others were increased up to 450mg based on reported experience and provider judgment.

In another large platform report, dosing was described as starting in the 300–600mg range, though the study also noted that dosing was not handled as one fixed-dose procedure.

So 300mg sits inside the reported sublingual/RDT/lozenge record.

But that does not make 300mg “safe,” “high,” “low,” “normal,” or “right.” Those words need more context than the milligram number can provide.

300mg once weekly is not the same exposure pattern as 300mg twice weekly.

300mg as a first dose is not the same as 300mg after dose adjustments.

300mg as a rapidly dissolving tablet is not the same as 300mg swallowed in a capsule.

Same number. Different dosing story.

400mg is near the upper end of one reported sublingual lozenge range, but it is not the highest number in the sublingual record.

One real-world lozenge report described a standard session dose of 150–200mg, with a broader range of 50–400mg. In that report, 400mg was the top of the range.

Other real-world RDT/lozenge reports described initial or adjusted ranges reaching 450mg or 600mg.

That is why “Is 400mg high?” needs a careful answer:

400mg is high compared with a 150–200mg lozenge session. It is not higher than every sublingual/RDT/lozenge dose reported in the record.

The evidence quality matters here. Much of this sublingual ketamine dosage record comes from real-world programs, not tightly controlled dosing trials. That makes the numbers useful for orientation, but weaker as protocol anchors.

Think of the research record like a road map. The well-marked highways are controlled and structured studies. Some sublingual data is more like a road drawn from traffic reports: useful, but not the same as a surveyed route.

The plain meaning: sublingual ketamine numbers can help you ask better questions, but they should not be treated as instructions.

Ketamine troche doses are often reported in the 150–600mg range, but the strongest usable troche/lozenge/RDT data is mostly real-world rather than controlled-trial evidence.

That matters because “troche” searchers are usually not asking an abstract research question. They may already have a prescription in hand. They may be staring at a package that says 200mg, 300mg, 400mg, or 600mg and trying to figure out whether that number makes sense.

A ketamine troche dose should not be compared directly with a swallowed capsule dose, an IV dose, or Spravato.

The troche is the package. Bioavailability is how much of what is in the package actually reaches the bloodstream. The milligram number tells you what is inside the troche. It does not tell you how much your body ultimately receives.

That is why ketamine troche bioavailability matters — and why it is less predictable than most patients realize. In practice, most people do not hold lozenges for the full recommended time before swallowing. That means real-world sublingual bioavailability typically falls somewhere between the 17 percent you would get by swallowing it and the 30 percent you would get from full sublingual absorption. The gap depends on how long you hold it. Same number on the label. Different amount reaching your bloodstream.

A troche, lozenge, or RDT is meant to dissolve in the mouth. Some exposure may come through the tissues in the mouth. Some may be swallowed. The exact instructions, dissolve time, saliva, swallowing, formulation, and clinic protocol can all change what the same milligram number means.

The milligram number tells you how much ketamine is in the package. It does not tell you how fast the package opens, where it opens, or how much gets through.

The research record cannot tell you what ketamine troche dose to take.

It can tell you what has been reported:

• •

  150–200mg per session as a standard lozenge dose in one real-world report

• •

  50–400mg as the broader range in that same report

• •

  300mg as an initial RDT dose in one real-world telehealth report

• •

  300–450mg as an initial or adjusted RDT/lozenge range

• •

  300–600mg as an initiation range in one large retrospective report

That is the useful answer. Not what you should take. What the record shows.

No. They belong in the same general under-the-tongue or in-the-mouth family, but they should not be treated as identical.

Troches, lozenges, rapidly dissolving tablets, and wafers can differ in how they dissolve, how long they are held in the mouth, how much is swallowed, and how each program adjusts dosing.

That is why “300mg sublingual ketamine” is not a complete dose description.

The better description is:

300mg of what form, held how, swallowed or spit out, how often, and adjusted by whom?

Without those details, the number is only the label. It is not the full dosing picture.

Ketamine troche doses often look higher because raw milligrams do not travel the same way through every delivery system.

An IV infusion sends the drug directly into the bloodstream. A swallowed capsule has to go through the gut and liver. A troche, lozenge, or RDT sits somewhere else on the map: dissolved in the mouth, partly absorbed there, and often partly swallowed depending on instructions.

That is why 300mg as a troche does not mean the same thing as 300mg by IV.

Same cargo. Different route.

A delivery truck, a mail slot, and a fire hose can all move something from one place to another. But nobody would pretend they deliver it the same way.

The plain meaning: ketamine troche dosage numbers often look large because the dose printed on the troche is not the same as the amount your body receives as active exposure.

This sublingual ketamine dosing chart shows the under-the-tongue, RDT, wafer, lozenge, and route-ambiguous rows from our 26-study analysis.

This table is less certain than the strongest oral-dose table because most of these rows come from real-world programs, open-label reports, retrospective data, limited dose reporting, or route-ambiguous records rather than tightly controlled dosing trials. We include it anyway because these numbers are still useful reference points for patients trying to understand whether a dose like 300mg or 400mg appears in the research record.

It is a sublingual ketamine dosage chart, not a dosing guide. The point is to show what was reported and where the record is unclear.

The cleanest takeaway from this sublingual ketamine dose chart is not that one number wins.

The takeaway is that sublingual ketamine dosing is usually reported in higher raw milligrams than swallowed oral ketamine, but the evidence base is also less settled and more platform-heavy.

That combination is exactly why patients need a chart. Without it, 300mg can look terrifying, ordinary, or meaningless depending on what you compare it to.

This chart separates troche, lozenge, and RDT-style reports from swallowed oral ketamine. That separation matters. If the form changes, the dose comparison changes.

The ketamine troche dosage chart does not show one standard dose. It shows a real-world dosing landscape.

For patients, that is still useful.

If your troche dose is 150mg, the chart shows that number in relation to a 150–200mg lozenge standard reported in one program.

If your troche dose is 300mg, the chart shows that 300mg appears repeatedly in RDT/lozenge-style reports.

If your troche dose is 400mg, the chart shows that 400mg is the upper end of one lozenge range, while other RDT/lozenge reports go higher.

If your troche dose is 600mg, the chart shows that 600mg appears in one large retrospective platform report as part of an initiation range, but that report did not use a simple fixed-dose procedure.

That is the point: the number only starts the conversation.

• ?

  Is this a troche, lozenge, RDT, or wafer?

• ?

  How often am I taking it? Zero controlled trials used once-weekly dosing. If you are taking sublingual ketamine once weekly and it is not working, you may not have failed the drug — you may have failed a frequency the research never validated.

• ?

  Am I supposed to swallow, spit, or hold it for a specific time?

• ?

  Is this a starting dose or an adjusted dose?

• ?

  Does my prescriber know my weight, and is it factoring into my dose?

• ?

  What evidence is my prescriber using for this schedule?

A troche dose without form, schedule, and instructions is only half a dose. It tells you the number on the package. It does not tell you the whole treatment design.

Why Oral, Sublingual, IV, and Spravato Doses Cannot Be Compared Directly

Here is the question patients ask constantly, and almost never get a straight answer to: if Spravato is 56mg and my troche is 300mg, why are the numbers so different? If IV ketamine works at 0.5mg/kg — roughly 35mg for an average adult — why does my lozenge say 200mg on the package?

The answer is not that one product is stronger or weaker. The answer is that the milligram number on any ketamine product describes what is in the package, not what your brain ultimately receives. Route, compound, and clinical context transform the same milligram number into completely different pharmacological events. Comparing them without adjusting for those differences is like comparing the speed of a car, a boat, and a plane by how much fuel they burn per mile. The unit looks the same. The systems are not.

The table below shows the four routes side by side. The detailed explanations follow.

IV ketamine is the gold standard in the research record because it removes all the variables. The drug goes directly into the bloodstream. There is no liver to metabolize it first, no mucosal tissue to absorb it partially, no gut transit to delay it. What you inject is what arrives. Bioavailability is approximately 100%.

The standard IV antidepressant dose is 0.5 mg/kg — roughly 35mg for a 70-kilogram adult. At that dose, peak plasma levels are reached in minutes. The dissociative experience that often accompanies IV ketamine infusions is a direct consequence of that rapid, high peak concentration.

The IV dose is the reason all other ketamine doses look large by comparison. 35mg by vein produces a specific plasma concentration. To match that concentration through a route that wastes most of the drug before it reaches the bloodstream, you need to start with far more milligrams. The math explains the numbers. It does not make 300mg sublingual and 35mg IV the same thing — they are not — but it explains why the gap exists.

Swallow a ketamine capsule and the liver intercepts it before it reaches circulation. The liver’s enzymes — primarily CYP3A4 and CYP2B6 — metabolize approximately 80 to 84 percent of the dose on this first pass. Of every 100mg in the capsule, roughly 16 to 17mg reaches the bloodstream in its active form.

That is oral bioavailability: approximately 16 to 17 percent.

The practical consequence: a 150mg oral dose delivers roughly the same systemic ketamine exposure as a 25mg intravenous dose. Peak plasma levels arrive more slowly — typically 20 to 45 minutes after ingestion — and at a lower ceiling than IV. That attenuated peak is why most patients taking oral ketamine report little or no dissociation. The drug never spikes high enough to produce the acute psychedelic experience that characterizes an IV infusion.

There is a partial compensatory mechanism worth knowing. First-pass metabolism also produces norketamine — the primary active metabolite — in substantially larger quantities via oral than intravenous administration. Norketamine has demonstrated independent antidepressant properties in preclinical research and persists in plasma longer than the parent compound. This partially explains why oral ketamine can produce meaningful antidepressant effects at doses that appear pharmacologically modest when compared only on the basis of the parent compound.

That said, 150mg swallowed and 150mg injected are not remotely the same treatment. The number is the same. The pharmacology is not.

Holding a ketamine lozenge under the tongue — rather than swallowing it — lets some of the drug absorb directly through the oral mucosa, the highly vascularized tissue lining the mouth. That direct absorption bypasses the portal circulation and the first-pass hepatic metabolism that costs the swallowed route most of its dose.

The result is a higher bioavailability: approximately 30 percent for fully sublingual absorption, compared to 16 to 17 percent for swallowed.

That 30 percent figure is a ceiling, not a guarantee. In practice, most patients do not hold lozenges for the full recommended dissolution time before swallowing. Saliva accumulates. The lozenge gets swallowed early. The actual bioavailability falls somewhere between the 17 percent swallowed estimate and the 30 percent sublingual estimate — variable from session to session and patient to patient, depending on hold time, saliva volume, formulation, and technique.

This variability is one reason the same sublingual dose can produce different experiences in the same patient across different sessions. The milligram number on the package is fixed. The amount that reaches the bloodstream is not.

At 300mg sublingual with full hold time, effective systemic exposure is approximately 90mg. At 300mg swallowed, it is approximately 50mg. At 300mg intravenously, it is 300mg. Three identical milligram numbers. Three different pharmacological events.

Spravato is not a more convenient version of the ketamine in a compounded sublingual lozenge. It is a different drug delivered by a different route under different clinical conditions. Comparing its 56mg dose to a 300mg troche without accounting for those differences produces a number that is technically accurate and practically meaningless.

There are three layers to the distinction.

Layer One: The Compound. The ketamine in compounded oral and sublingual prescriptions is racemic ketamine — an equal mixture of two mirror-image molecules, the R-enantiomer and the S-enantiomer. Spravato contains only the S-enantiomer, called esketamine.

These two molecules are mirror images of each other — like a left hand and a right hand. They look nearly identical. They do not fit the same receptor in the same way. The S-enantiomer binds to NMDA receptors with approximately four times greater affinity than the R-enantiomer, according to a 2025 meta-analysis in Frontiers in Pharmacology. Because racemic ketamine is a 50/50 mixture of both, esketamine is roughly twice as potent per milligram as racemic ketamine at the receptor level.

That means 56mg of Spravato is not pharmacologically equivalent to 56mg of a compounded lozenge. It is doing more at the receptor, per milligram, than its racemic counterpart would.

Layer Two: The Route. Spravato is administered as a nasal spray — absorbed through the nasal mucosa, which has its own vascular bed and its own absorption characteristics. According to the FDA prescribing information, mean absolute bioavailability following intranasal administration is approximately 48 percent. Peak plasma concentration is reached 20 to 40 minutes after the last spray.

That 48 percent bioavailability is higher than sublingual ketamine at its best and nearly three times higher than swallowed oral ketamine. At 56mg with 48 percent bioavailability, approximately 27mg of esketamine reaches systemic circulation. At 300mg sublingual racemic ketamine with 30 percent bioavailability, approximately 90mg of racemic ketamine reaches circulation — but at roughly half the per-milligram receptor potency. The dose comparison is not 56 versus 300. It is a multi-variable pharmacokinetic problem with no simple one-number answer.

Layer Three: The Clinical Context. Spravato is administered exclusively in certified healthcare settings under a federally mandated Risk Evaluation and Mitigation Strategy (REMS). Patients self-administer the nasal spray under direct clinical supervision and are monitored for a minimum of two hours after each dose for sedation, dissociation, and blood pressure changes. In clinical trials, 48 to 61 percent of Spravato-treated patients developed sedation requiring monitoring. The drug must be used in combination with an oral antidepressant.

This is not a bureaucratic detail. The clinical context is part of the treatment. Spravato at 56mg in a monitored medical setting is a different therapeutic event than 300mg of sublingual ketamine taken at home on a couch, unsupervised, once a week.

Why Spravato matters for insurance. Spravato is the only ketamine-related product with full FDA approval for treatment-resistant depression and the only one that most insurance plans cover as a standard benefit. Compounded oral and sublingual ketamine has no FDA approval for depression, which is why insurance coverage for those products is inconsistent and often denied. For many patients, Spravato is not a pharmacological preference — it is the only financially accessible option. Understanding that its 56mg dose cannot be directly compared to a 300mg troche is not academic. It prevents patients from concluding they are on a weaker treatment, or from using Spravato’s insurance coverage as evidence that sublingual ketamine at five times the milligrams must be dangerously high.

When you see a ketamine dose — any dose, from any source — three questions determine what that number actually means:

• •

  What compound is it? Racemic ketamine and esketamine are not interchangeable milligram for milligram.

• •

  What route is it? Bioavailability ranges from 16 percent (swallowed) to 48 percent (intranasal) depending on delivery method.

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  What is the clinical context? A supervised infusion center, a REMS-certified clinic, and an unsupervised living room are not pharmacologically equivalent environments.

No number stands alone. A 56mg Spravato session, a 300mg sublingual lozenge, a 150mg swallowed capsule, and a 35mg IV infusion can each produce meaningful antidepressant effects through related but distinct mechanisms, at different plasma concentrations, in different patient populations, under different safety conditions. They are not rungs on the same ladder. They are different ladders leaning against the same wall.

How much ketamine should I take for depression?

There is no official oral or sublingual ketamine dose for depression. That is why this feels so confusing. The best reference point is not one magic number, but what studies have actually used. In the 26-study record reviewed here, swallowed oral ketamine often centered around weight-based doses like 1mg/kg — about 70mg for a 154-pound adult — while sublingual, troche, lozenge, and RDT doses were often reported in much higher raw milligrams.

Is my ketamine dose too low?

A ketamine dose can look low without actually being low, depending on the route, schedule, body weight, and formulation. For swallowed oral ketamine, 50mg appears at the low end of the research record. But 50mg once a week is very different from 50mg daily, and 50mg for a 110-pound patient is different from 50mg for a 250-pound patient. The number alone does not tell the whole story.

Is my ketamine dose too high?

Maybe — but you cannot tell from the milligram number alone. A dose that looks high in swallowed oral ketamine may be ordinary in a sublingual troche or RDT program. For example, 300mg would be very different if swallowed as an oral capsule than if held under the tongue as a troche or rapidly dissolving tablet. Route, body weight, schedule, and instructions matter.

What is a normal ketamine dose for depression?

There is no single “normal” dose. In the research reviewed here, common reference points included about 70mg oral ketamine for a 154-pound adult, 150mg as a fixed oral dose in some protocols, and 150mg to 600mg in sublingual, troche, lozenge, or RDT reports. “Normal” depends on which form of ketamine you are taking and how often you take it.

Why is my ketamine dose so high?

Sublingual ketamine, troches, lozenges, and RDTs often use higher milligram numbers because your body does not absorb them the same way it absorbs IV ketamine or swallowed ketamine. The number printed on the dose is not the same as the amount that reaches your bloodstream. That is why 300mg sublingual ketamine is not the same as 300mg IV ketamine.

Is 150mg oral ketamine a lot?

150mg oral ketamine is one of the clearest fixed-dose oral reference points in the studies reviewed. But it is not the same dose for every body. In a lighter person, 150mg can land near the upper end of the structured oral research range. In a heavier person, it can land much lower. Same bottle, same number, different body-weight dose.

Is 300mg or 400mg sublingual ketamine a lot?

300mg is not an outlier in the sublingual ketamine reports reviewed here. It appears in real-world RDT and lozenge programs. 400mg is higher than some reported lozenge standards, but it is still within the broader sublingual/RDT record. That does not mean either dose is right for you. It means those numbers are not automatically shocking once route and formulation are considered.

Why did my provider give me a dose that does not match what I found online?

Because oral and sublingual ketamine dosing is not standardized. Different providers use different protocols, different formulations, different schedules, and different assumptions about body weight and dose adjustment. Some use fixed doses. Some use weight-based dosing. Some telehealth programs use once-weekly schedules, even though the article notes that the positive controlled trials used more frequent dosing patterns. The mismatch does not automatically mean your provider is wrong — but it does mean the dose deserves context.