Reminds me of chifir, which is still popular in Russian and easter-euro prisons

"Ultimately, making chifir involves brewing a great deal of black tea and for a long time. It may be left to brew overnight and drunk either hot or cold."

They use it as some sort of substate for alcohol but I'm not sure of exact effect. I know it causes extremely bad teeth rot after multi year consumption.

https://en.wikipedia.org/wiki/Chifir