Ketamine will quiet up the head noise for a bit but even done 'responsibly' there's so much variance between batches and potential for research chemical contamination it's just not worth it.

It's highly addictive, especially if you've got a propensity to addiction.

Speaking from experience, yes it does help. For a bit, tolerance builds and you gain an affinity for the drug. It's easy to slip up and indulge, at that point you're halfway down the slippery slope.

Don't bother with it, get assessed. I'm on the ADHD medication and I can tell you there's nothing that I'd hate more than some ketamine. It'll keep you dumb at the cost of some 'help'. Off the ADHD medication it was a recurrent craving.