Am I correct in stating that paliperidone is an active metabolite of the older neuroleptic rispiridone BUT allows for a long-chain ester (palmitate) prodrug to provide a depot formulation?
If so, I am a little surprised as to my untutored eye, that's going to produce an extremely lipophilic prodrug. Haloperidol depot is the n-decanoate (10 carbon) ester whereas the palmitate (16 carbon) will be even more lipophilic.
All other things being equal, that's going to have a tremendously long half life. Now I don't know if other metabolic processes mean that the palmitate doesn't have the same half-life as haloperidol decanoate but I don't know of any such metabolism.
On a different topic, I have known some people who had been prescribed depot injections of various neuroleptics. In every single case, I asked why, after decades, they were STILL being given depot injections since they were also prescribed medications that had to be taken multiple times a day and as far as I know, they didn't struggle to manage those other medications. I'm just asking if, while a depot MAY be appropriate in certain situations, do people feel they needed the depot? Or Are people essentially being told that either they accepted the depot or could end up either sectioned or in breach of a community drug treatment order (CDTO).
Because this thread certainly doesn't read as people being happy with the outcomes.