It arrived today and I took 100 mg at 11 am and another 100 mg 30 min later.
Wasn't that sleep deprived but wanted to test it. I've been really awake all day, though not super fit like when you just had a good portion of sleep. More like when you take a lot of caffeine to stay awake. But more powerful. Also got a little more done than usual, but not much. Maybe a little effect on my focus? Definitely not much.
Now the bad stuff: It significantly raised my heart rate. 1-2 hours after taking it, my pulse went to 130 (normally at 80-90). Lasted maybe half an hour when it went to 115. Probably stayed at about that level for the next few hours. But for the last 2 hours its been up at 130 again (it's 10 pm now).
When I went upstairs fast (like always, just 1 floor) it jumped to 140-150. I'd probably collapse from my usual light biking workout right now. Not cool.