Eternal Prohibition: Averted, because no-one in the Empire would consider it reasonable to ban anything that, say, didn’t cause immediate homicidal mania in the first place. Your psychochemistry is your own business, and no-one else’s – except the plentiful dealers in recreational chemistry. And enhancement chemistry, like nootropics, mnemotropins, etc., etc. Some of which are even used in breakfast cereal.
Don’t even ask what they put in the fruity oaty bar…