It has been widely reported that Bellmarsh medicates its political prisoners. It has also been reported by everyone who sees him that Assange is medicated.
Maybe Big G's in on it too.
https://classconscious.org/2019/06/29/protest-at-twitter-hq-...
There is a media block (the UK can do that quite simply) on any reporting about Assange's health and conditions in Bellmarsh:
https://www.opednews.com/articles/Media-Block-on-Assange-s-T...
There is a definite campaign to torture/brainwash Assange while he is in Bellmarsh, as discovered by a UN investigator:
The rest is unsubstantiated conspiracy theory.