I've found the cold extraction route to be a great way to get a stomachfull of tannins and a decidedly not-great way to get high. You'd be better off boiling it. But to answer your question, I think you'd probably be safe to drive pretty much immediately if you take it without harmalas.
I don't want comfort. I want God, I want poetry, I want real danger, I want freedom, I want goodness. I want a clever signature.