I bought some 's-isomer' lately that I would have said is racemic if it weren't for the assurances of the seller, and his universally good reviews from other customers - though he doesn't yet have many. I had up to a gram one night without k-holing and then another night had a 250mg line to check it and still no k-hole. In fact, I could get up and walk around without the usual difficulty. I can feel that it's ketamine, it just doesn't have much effect. Diminishing effects actually seem to have been ongoing recently and I don't even use it that much. I experienced minimal effects from some k I bought from another seller too, whose stuff I think I k-holed on before - though in that case, another customer pointed out it was racemic, so maybe they changed their supply. I mean, there's always the chance the dealer is wrong and it is just racemic - but could there be another reason? Like caffeine maybe? I probably drink stronger coffee than I used to - but this would be a stretch! What else could it be? Are there certain types of s-isomer that you need to take more of to work?