Self-medicating in general is usually not advisable, especially not on a more regular basis. (There are, full disclosure, circumstances where I might self-medicate with alcohol, but they are definitely a rare exception, not a regular thing. Like less than a handful times ever so far rare exception.) One of the great tragedies of the war on drugs is how much it has limited research on drugs, along with it being pushed underground where there’s no quality assurance. So not only do we not necessarily have exhaustive data on reactions and interactions, there’s also always the risk of the product being cut with something else that changes how you metabolize it, or which you have a poor reaction to. Impurities wouldn’t so much be a concern with eg. marijuana from a legal dispensary or alcohol from a store, but “illegal” drugs (including marijuana given it’s still federally illegal) still have the problem of limitations on research.
Everyone will also react differently to intoxicants, so self-medicating based on other people’s experiences is an especially poor idea.