Just Don't... You will have a bowel obstruction well before you get high. Lope can cross the BBB, but it's P-Glycoprotein that pumps it out almost instantly. Therefore, only a very very very minimal amount of lope will bind with the opioid receptors in the nucleus accumbens This is why some people feel some effects from large doses, but they aren't pronounced. The only way to even possibly get high off lope is if you take a potent dose of a PGP inhibitor; doing so will also open your brain up to a world of crap too, so don't do it. I just thought that I needed to explain this so you actually know that it won't work and why it won't work from a objective scientific position.
A higher serum level of lope will cause more to cross the BBB and have more effects, but they'll still be minimal; the dose required to produce a high or something of the sort would also likely cause ileus or a bowel obstruction which is a serious issue and will cause you a ton of pain for you're below average buzz. Overall, if you're this desperate, it's time to either quit or score... Paralytic ileus can kill, there have been several deaths caused by loperamide induced paralytic ileus.
The risk is very high and the reward is minimal, this is equatable to jumping off a tall building in order to get a rush from those 3 seconds of flight only to splat on the ground.