This is relative in some ways. I myself enjoy setting aside time for the trip itself but also time for contemplation, journaling or otherwise integrate for at least a couple hours afterward. Sometimes experiences can be pretty intense and emotions can be equally as intense leading me to need even more time to acclimate back to the world, calm down my emotions, breathe and focus on taking care of myself. I think it important to check your mind and body afterward. All systems check and then go back into life.
Each to their own. I know people who could care less about integration and all this. It's a matter of approach I suppose. I create ceremony, intentions and really dive in with a heavy amount of respect for where this molecule can take you. I don't take it lightly. For me it's serious sacred work.
To answer your question more simply. You can be back to baseline in a matter of minutes. I have often looked at the clock afterward and surprised to find a mere 8 mins had passed while the experience itself felt like weeks or months or eons had gone by, maybe even forgetting I was a human. I usually feel a nice afterglow in most cases and can resolve normal duties in life within the hour if needed.
Good luck and happy travels!
'There is an area of the mind that could be called unsane, beyond sanity, and yet not insane. Think of a circle with a fine split in it. At one end there's insanity. You go around the circle to sanity, and on the other end of the circle, close to insanity, but not insanity, is unsanity.' -Sidney Cohen