MDMA, sure, would have severe consequences if consumed so much.
Psychedelics, such as mushrooms or LSD, would cause hardly any harm and simply would stop working due to tolerance build up, unless the user keeps doubling the dose every time.
6 days of LSD a week or even weekly can easily make you believe really weird things (often with a spiritual bend), though it depends on the dosage. I'm pro LSD but I've seen a ton of people change massively from overly frequent use.
MDMA, sure, would have severe consequences if consumed so much.
Psychedelics, such as mushrooms or LSD, would cause hardly any harm and simply would stop working due to tolerance build up, unless the user keeps doubling the dose every time.