Levetiracetam (extended-release)
Levetiracetam (extended-release). Extended-release formulation of levetiracetam — same SV2A binding mechanism, once-daily dosing improves… Oral half-life 7 h.
Extended-release formulation of levetiracetam — same SV2A binding mechanism, once-daily dosing improves adherence. Same pharmacology as IR levetiracetam.
PK: NOT THE EXTENDED-RELEASE TRANSPLANT DEFECT, AND NOT ITS REVERSE. Volume and half-life are DISPOSITION parameters, formulation-independent by construction, so an extended-release record legitimately shares them with the immediate-release sibling — AND THE CITED PAPER PROVES IT ITSELF: "levetiracetam XR and IR were bioequivalent with respect to AUC((0-t)), AUC(infinity) and C(max)". Those values are substantively correct and merely uncited. THE ONE GENUINELY FORMULATION-SENSITIVE PARAMETER IS THE WRONG ONE: the stored absorption rate implied a peak at 5.5 h against this record own citation verbatim "The median t(max) was delayed from 0.9 to 4h", and it is not an immediate-release value either. The replacement is back-derived to reproduce that verbatim 4 h exactly and is flagged as derived; a zero-order duration would model an extended-release tablet better still and is logged. AN OUT-OF-SCOPE FINDING ON THE SIBLING IS RECORDED: immediate-release levetiracetam own published quartet sits 1.31-fold below the feasibility floor, so it is mildly unrepresentable in one compartment too.
Pharmacokinetics
- Oral — t½ 7 h · F 100% · ka 0.508 h⁻¹ · Vd 38 L
Sources: PMID:19264451