It's not a huge stretch to think that if a prescription drug can be of great benefit to someone, (like a drug treating suicidal depression) that the same cannot be said of a drug that is not owned and branded by pharmaceutical companies. All drugs are not equal. Some have a greater risk of abuse, higher risks of addiction, and are more detrimental to your health than others. With these drugs that are illegal it's especially important for users to educate themselves on their pro's and con's and whether their negative effects outweigh their positives for them personally. For many people they are of great benefit and used responsibly, but most people do not hear those stories. When they're used irresponsibly by individuals, it does make headlines and it perpetuates a negative bias in our society toward them. Drugs like psychedelics especially give you just what you're looking for here. They hold the ability to rid yourself of bias and consider things from another perspective. Speaking personally that is of great benefit to me. Heightened unbiased introspection toward bettering yourself and helping others. If you read around more and educate yourself further on this topic I think you'll better understand yet. Here is a great link on psychedelics in particular. As for what it's like to take a heavy dose... it's intense. And it can be frightening. But also incredibly beautiful and unlike anything you could imagine. Days afterward? You may be a bit sluggish if you were overwhelmed with it's intensity but just incredibly grateful that such a thing exists.