Not very long, in fact only once, and that was 25 mcgs, along with a whole bunch of other stuff. I wrote about it somewhere here. Lemme see..
That’s the part you’re probably interested in. To add a little to that, it really actually slowly built up. First he was just really touchy and hanging on the shoulder of my friend’s dad. But then after the parents and older guests left, the girls started dancing with each other. Then they started giving each other lap dances, learned a little salsa, and so on. It began to get outta hand around the time my shit faced friend, sitting on the couch, reaches up and grabs two girls, one in each arm, and pulls them down onto the couch…well sorta more onto him, onto the couch. From that point, it just completely got out of control. This is keeping in mind that I wasn’t really in their presence for the prior hour with the p83 on. It was only till after I rejoined them that things kinda turned this way.
Also, I didn’t mention it to the Dr when I was talking about body language, but he had was actually invading my space to the point where I had literally backed up 3 feet. The thing is that it happened over an hour or so, so he had no idea. The only reason I realized at first was because I noticed I had to reach further and further for my drink. 
I haven’t been in too many situations where I’d feel comfortable sending out that kinda vibe since then, especially if what I’ve seen so far is any indicator of what p83’s capable of.. 