Paliperidone
Paliperidone. Atypical antipsychotic; D2 / 5-HT2A antagonist. It is the major active metabolite of risperidone (9-OH-risperidone) and is largely… Oral half-life 24 h.
Atypical antipsychotic; D2 / 5-HT2A antagonist. It is the major active metabolite of risperidone (9-OH-risperidone) and is largely renally cleared. Oral ER tablet + 1-/3-month palmitate depot.
PK: CLASS 6 CONFIRMED, WITH RECORD-INTERNAL PROOF. V 487 L is the label APPARENT volume and no intravenous paliperidone volume exists — the only abstract reporting one calls it "Apparent clearance and apparent volume of distribution". The proof that at least one row was wrong sat inside the record: the SAME 487 L was on the depot row beside F 1, and one number cannot be simultaneously apparent and absolute. F is now pinned to 1 and the measured 28% recorded here, verbatim from a paper the record did not cite: "The marketed extended-release formulation has 28% bioavailability". THE FLIP-FLOP WAS BACKWARDS: the stored ka 0.08 exceeds the elimination rate, making the model elimination-limited, while the real extended-release half-life is ABSORPTION-limited; and 0.08 implies a 19.9 h peak against a cited "maximum plasma concentrations occurring at 24 hours". THE DEPOT ROUTE IS REMOVED — it was hung on an ORAL MASS-BALANCE study ("a single dose of 1 mg of [14C]paliperidone ORAL SOLUTION") that never used the route, never used the ester, and reports no pharmacokinetic parameters at all; its 672 h release duration is the one-month dosing interval.
Pharmacokinetics
- Oral — t½ 24 h · F 100% · Vd 487 L
Sources: PMID:19713555, PMID:18227146, PMID:8935801, PMID:29776316, PMID:20589922, PMID:7531854