## [t3_28sai9](https://www.reddit.com/r/explainlikeimfive/comments/28sai9/eli5_why_are_all_drugs_bad_why_cant_there_be_a/)
Why can't there be a drug that is as harmless as drinking a glass of water but activates the pleasure sensory part of the brain? I've never understood why, regardless if its addicting or not, there always has to be a negative to the positive with any drug. 


And please don't flood this thread with "WEED!". I said 0 adverse effects. Marijuana's great and all, but it's far from completely harmless.  


I guess in other words, why hasn't the "perfect drug" been developed? 


EDIT: I fixed the "irregardless". Jesus. 

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