> Ketamine is made up of mirror image molecules and esketamine is the right-handed molecule.

Esketamine is their cutesy way of saying the word s-ketamine. The s- comes from the Latin word "sinister" which means this is the left-handed enantiomer, not the right-handed one.

It is stupidly expensive, given how generic ketamine itself is. In our case, sleep apnea treatment proved to be a much better option than that drug, as it was just hiding an underlying condition and the treatments only last for maybe a week or two anyway.

I think there have been some people using ketamine off-label, but I don't know much about that. It does need to be tightly controlled because it can cause breakthrough psychosis in some patients. They try to screen those out, but that's not as effective as one might hope given my experience of seeing that fail. And it that was very nearly a fatal mistake.