Dute,
You should definitely feel effects from yohimbe bark, I’ve never tried pure yohimbine but I’m sure you’d feel something also.
I really like yohimbe bark, but I can’t take it for more than a few days because of the side effects. The first side effects (for me) are slight facial flushing, a feeling of taking too much caffeine and sometimes a racing heart feeling, if I take two pills I also sweat a little. Of course there’s also the horny feeling and the incredible ease in getting a boner, similar to viagra. Over the course of a few days I also get irritable and a little paranoid, I start thinking about sex alot more than work and have to stop taking it. Don’t take it after 5 pm. For me it lasts 6-9 hours and can keep you awake. So my advice is only to take it occasionally.
I like GNC’s standardized version with 4% Yohimbine alkaloids so one tablet is equal to 9mg yohimbine. I’ve tried other brands and some work and some don’t. Look for an actual equivalent amount of yohimbine alkaloids. If you do try it, start small and work up to it, like a half a pill at a time. Oh, I weigh 185lbs for comparison. Also, it does give me a little more energy (I’ve read african warriors used to take lots of it before battle) so it wouldn’t hurt before a game of hoops or a workout. I definitely wouldn’t take it if you have heart problems.