HDAC inhibitors have been discussed before on /r/nootropics and Longecity. I was part of a group buy for Vorinostat, which is a medication with a similar mechanism of action. I only took it once and had a positive experience where I felt very "child-like", in the way that the world seemed vivid and exciting. I haven't taken it since due to concerns about interactions with some of my other medications.

The primary goal of many of the people in the group buy were fear extinction and memory enhancement. I haven't seen much discussion on it since the initial excitement.

Here are the relevant threads:

http://www.longecity.org/forum/topic/90632-hdac-inhibition-m...

https://www.reddit.com/r/Nootropics/comments/596gbi/i_wrote_...