This is 2021 and literally any drug you can think of can be easily and relatively safely mail ordered to any deliverable address in the world, thanks to the wonders of ToR. So, drugs have never been more accessible.
I know one person who tried clinical Ketamine for tinnitus and had no improvement. My only relatable experience was with Methoxetamine, which I believe caused a significant (but short term) spike. Pramipexole is known to
cause tinnitus.
Brains are weird and some random person may have had a beneficial response to this. They may have had a spontaneous improvement unrelated to their weird drug use. They may be completely full of horseshit, it's hard to say.
I wouldn't attempt this protocol until I saw some clinical work around it. I
did consider a Ketamine regimen -- I could do it legally and safely at a nearby doctor's office -- but I am fairly dismal on the idea of it doing anything useful, and of course it would be much cheaper and easier to just get illicit Ketamine, but I'm a bit old for that
I've had tinnitus to some extent since I was 19. I used Ketamine at similar doses to what's described here for a period in ~2006-2007, and I do not remember any changes at all to my tinnitus, mostly just the world starting to turn into an incomprehensible cave that didn't have any words in it.
Well, it's actually a fairly serious script that they have to write, but these clinics are set up to do that. They are pretty closely FDA monitored and this is a DEA-pad script, though; if someone decided to just start randomly selling Ketamine to any "patient" that rolled up, they would find themselves getting rolled by DEA.