Mushrooms Key To Contact???
I agree with good points made in the posts above. I'd add that it is possible that some non-humans (ETs, transdimensionals, entities using hidden dimenssions) could be malevolent.
Take for example ourselves, a evolved, intelligent, opportunistic and predatory species (homo sapiens) who will exploit and kill others if it suits us, or when looking for a tasty snack. If we ended up as us, it is probable there are some folks JUST LIKE US sharing the universe.
So if you use some psychoactive enabler to meet 'others' you'd have to make realistic preparations to deal with any bad ones.
Even better, member ChrisPerridas idea: check up on writings of researchers who have already trodden that path, avoiding any risk to yourself.
A man of Trachis' warning:
"When the Barbarians discharge their arrows they obscure the light of the sun by the multitude of the arrows"
Dienekes of Sparta's reply:
"Good news, for if the Medes obscure the light of the sun, the battle against them will be in the shade"
~Dienekes, Battle of Thermopylae 480 BCE [Herodotus 7.226]