Have you heard of ketamine making people "immune" to alcohol and other drugs like hallucinogens?
This whole subject is really interesting and you should at least check out some Wikipedia articles:
https://en.wikipedia.org/wiki/NMDA_receptor_antagonist
I had found the NMDA receptor connection, but so far not any mention of long term (four to six months) of alcohol insensitivity after ketamine use. If there is one, I'm unable to find it.
Some new information in those Wikipedia links, about other neuroreceptors.