How long is it?
I personally would judge my next move based on how the piece looks once you pull it out.
A. It is short and only in the tread block, I would continue to ride it, no patching.
B. Its long and went all the way through, I would replace the tire before I went fast, and if necessary patch it with a 3 dollar patch kit and go a bit slow until the new tire arrived.
Personally, I like to consider a patch as an excellent rescue action, just not a permanent solution...