You'd have to stretch the definition of "occasional" to make this statement supportable. Clinical studies on the topic focus on chronic heavy users, whose usage far surpasses the dosing used by the median recreational user and typically persists for years. (In fact, most studies focus on recreational users who are using near-clinical levels, which is an order of magnitude more than the typical recreational dose, and doing so with regularity).

While it's possible that occasional use can cause issues, it's far from established fact, and the widespread usage of large doses of ketamine in inpatient settings for decades without reports of issues for those users would actually suggest otherwise.

Is that so? For ambien it's the opposite, usually the recreational dosage can be a lot higher for some users than a clinical dosage (5 or 10mg)

Correct. What you are saying is true for almost all drugs: recreational doses are typically higher than clinical doses. Ketamine is the exception.

The recreational dose for a ketamine-naive user[0] is somewhere between 5-20mg. The clinical dose for depression is 86mg (not a typo), which is sometimes doubled, and the clinical dose for anesthetic purposes (which is what ketamine is mostly used for) is between 500mg-1g. The latter is IM injection, so it's also much more bioavailable than the first two (ie, the effective dose differential is even higher).

Of course, regular users develop a tolerance and heavy chronic users of ketamine can do more. But that's due to tolerance, not representative of the typical baseline recreational dose. (If they were to need ketamine for inpatient anesthetia, they would need absolutely massive doses for it to be effective).

[0] "naive" is not a judgmental term; it's the clinical term used to describe a user who has no prior experience with the drug, or who has no baseline tolerance (ie, whose prior usage is far enough in the past that it is no longer relevant).

To clarify: my understanding is that ketamine acts as a dissociative hallucinogen at lower doses and an anaesthetic at higher doses, so taking a higher dose will just knock someone out instead of giving them the dissociative/hallucinogenic effects.

> The clinical dose for depression is 86mg (not a typo), which is sometimes doubled, and the clinical dose for anesthetic purposes (which is what ketamine is mostly used for) is between 500mg-1g. The latter is IM injection, so it's also much more bioavailable than the first two (ie, the effective dose differential is even higher).

Ketamine is normally dosed based on body weight[0]. For depression IV, the dose is 0.1–0.75mg/kg/40mins, most commonly 0.5mg/kg/40mins. Clinical use in IM seems to be less consistent, with some clinicians using the same range and others doubling it, so the 86mg could be used for a wide range of body weights.

[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6023575/table/T...

[1] https://www.psychiatrist.com/jcp/depression/ketamine-for-dep...

If we're being specific, the FDA-approved treatment of ketamine for depression is a fixed 84mg dose. It is not adjusted for body weight.

(I did invite irony by saying that it wasn't a typo - it's 84 and 56 for redoing, not 86 and 54).

The fact that they're both dissociatives doesn't mean they're substitutable in any given context.

Dextromethorphan is a much riskier drug overall than ketamine, in almost every measurable way. It's very easy to overdose on dextromethorphan, to the point where people routinely do it by accident while self-medicating for a cough. By contrast, it's actually quite difficult to overdose on ketamine - the LD50 is quite high, and a person would likely incapacitate themselves halfway through and be unable to finish.

They also have dramatically different effects - there are actually very few contexts in which both could be considered an acceptable choice for a given goal.

The bladder issues with ketamine are only documented for chronic heavy users. There's no clinical evidence of it for one-time use, and given the extensive use of ketamine in controlled settings for several decades, the absence of evidence is (in this case) strong evidence of absence.

On other hand I've been in, and had friends in, so-called "k-holes" because of doses of ketamine that were too high and the experience was ... awful. Imagine thinking you're dead, but you're still conscious.

Both are NMDA antagonists. Both provide emotional and physical dissociation. They are in the a similar class of experiences.

Psychotherapeutic doses of ketamine are not one-time. At least not from the reading I've been doing. They have been found to be more effective done over several sessions. I honestly worry about the potential for bladder damage because it has not been studied well and also this kind of treatment is something we're looking into for a loved one

It allows you to take a much lower dose of dextromethorphan and so have fewer undesirable side effects. It helped me cope with some chronic physical pain I was suffering with at the time (in addition to depression).

This is insane gouging, as you could literally make it yourself by getting a prescription for generic bupoprion and some store-bought cough medicine.