It's hard to say how long, it does take a day or 2 to kick in (when I said "immediately" I meant within a couple days when I start taking it. I probably shouldn't have used that term.)

I'm not very strict with medication so I tend to stop it when I don't have issues.

But especially in my elbows where I only have mild pain it seems to help a lot. In my wrists it doesn't as much, but I think the pain there is not totally joint-related.