Since the answer was had by the second or 3rd post, so as not to get anyone pants in a twist, I feel like I can tell my personal(surely not the only one here who’s experienced this)anecdote.
I’ve recently had a foot injury. It went all sideways. Ended up with a somewhat horrific surgery. Short, but nasty.
As I heal slowly, it was really getting to me. The surgeon sent me to the wound care place. After they were done screaming at the sight of my foot and causing me discomfort the wound care specialist( 
) sez, “LASER”.
So I’m carted to the bowels of the joint.
Put in what was similar to a dental chair.
Put little glasses on.
And they lasered me.
No pain. No fret. No blind eye. (No bill, 100% covered)
Went back 3 more times.
Can’t swear it sped things up.
They say it did. I really really want to believe it. So I will.
Not a substance, I suppose.
I do believe its legit.
I’ve found a bunch of info online that assures me its legit.