Therapeutic use for treating depression is one dose every several weeks, so there's no chance of addiction forming unless the patient decides to start using it recreationally - and even then, although some people do get mentally addicted to ketamine, it's fairly rare even among frequent users.
And my memory of reading up on this is that the current understanding of how ketamine works for treating depression is that it's something about the way the body processes & gets rid of the ketamine, it's not from the effects that the person taking it feels (unlike with psychedelics where it's the effects themselves that open up new neural pathways in the brain allowing therapy to potentially be more effective). And taking ketamine daily won't be more effective for treating depression. So I wouldn't expect many patients to go from the medical treatment to thinking "I want to start using this recreationally" (though if enough people get treated with it, of course a few people are bound to go down that path - but plenty of people already go down the path of choosing to use it for fun).
And my memory of reading up on this is that the current understanding of how ketamine works for treating depression is that it's something about the way the body processes & gets rid of the ketamine, it's not from the effects that the person taking it feels (unlike with psychedelics where it's the effects themselves that open up new neural pathways in the brain allowing therapy to potentially be more effective). And taking ketamine daily won't be more effective for treating depression. So I wouldn't expect many patients to go from the medical treatment to thinking "I want to start using this recreationally" (though if enough people get treated with it, of course a few people are bound to go down that path - but plenty of people already go down the path of choosing to use it for fun).