Celecoxib
Celecoxib. Selective COX-2 inhibitor → preserves GI-protective COX-1 prostaglandins → reduced GI bleeding vs non-selective NSAIDs. Tradeoff… Oral half-life 7.8 h.
Selective COX-2 inhibitor → preserves GI-protective COX-1 prostaglandins → reduced GI bleeding vs non-selective NSAIDs. Tradeoff: selective COX-2 inhibition shifts the PGI2/TxA2 balance toward thrombosis — CV risk concern (rofecoxib/Vioxx withdrawn 2004; celecoxib survived PRECISION trial). Sulfonamide — caution in sulfa allergy.
PK: the half-life of 7.8 h is verbatim and stands, labelled as the CYP2C9 extensive-metaboliser value (poor metabolisers give 11.5 h). F 0.4 is contradicted by the record own cited review, which states "the extent of absorption is not known", and no absolute bioavailability can exist because there is no intravenous formulation — so F is pinned to 1 and the volume stored as the published apparent 346 L, removing a double-division. ka 1 is dropped rather than replaced: a genuine value exists, an absorption half-life of 0.35 h, but it comes bundled with a 0.62 h lag this schema cannot represent, and a bare rate would predict onset too early. THE EFFECT-COMPARTMENT VALUE IS KEPT WITH ITS TITLE CORRECTED. It verifies exactly, but it is a PLASMA-TO-CSF TRANSFER constant rather than measured analgesic hysteresis; it was estimated as one POOLED value across three coxibs, two of which have since been withdrawn so the pooling can never be re-validated; and it applies to UNBOUND drug while celecoxib is about 97% protein bound, so feeding it a total-plasma concentration is a unit mismatch.
Pharmacokinetics
- Oral — t½ 7.8 h · F 100% · Vd 346 L
Sources: PMID:10749518, PMID:36318604, PMID:11816012, PMID:10701700