[collyw]

Are recreational doses significantly higher than prescription doses? Why the difference?

[jdietrich]

Yes. "Recreational" users rarely suffer from ket bladder - it's people with serious addictions who are ending up in urology clinics. Users are reporting taking anything from 5 to 15 grams per day; even assuming that it's of very low purity, that's still orders of magnitude more than the doses being used to treat depression.

[atomical]

Ketamine is toxic to the bladder at any dose. I haven't found any long term research on this topic.

[DanBC]

The research for depression used much lower doses of ketamine than recreational use. One UK clinic was using about 80 mg as a max dose. https://www.oxfordhealth.nhs.uk/news/first-uk-study-of-ketam...

A large recreational dose may be 250 mg.

This is partly because the recreational dose is looking for different effects, so they use more. And because people build up a tolerance.

[IntronExon]

It’s also a result of ketamine typically being used in the context of other drugs, especially stimulants.