"Today, Assange sits behind bars in a London prison under shocking conditions even a murderer wouldn’t expect. Renowned filmmaker and journalist John Pilger visited him there and fears for Assange’s life, noting he is held in isolation, heavily medicated and denied the basic tools needed to fight his charge of extradition to the United States"
The tweet also says he is isolated, not that he is held in isolation. Anybody in prison could be considered isolated from society, but held in isolation means something much harsher.
In the UK "medicated" has negative connotations, usually implying "medicated with psychotropic medications, often against the patient's will".
There's paperwork and procedures for that to happen, and I'd guess for a high profile person like Assange the prison is being careful to make sure all the paperwork is correctly done.
https://www.mintpressnews.com/media-blackout-imprisonment-es...