Raloxifene
Raloxifene. A benzothiophene selective estrogen receptor modulator (SERM): an estrogen-receptor antagonist in breast and uterine tissue but an… Oral half-life 33 h.
A benzothiophene selective estrogen receptor modulator (SERM): an estrogen-receptor antagonist in breast and uterine tissue but an agonist in bone, where it reduces osteoclastic resorption and preserves bone mineral density. Approved for postmenopausal osteoporosis and breast-cancer-risk reduction; used off-label in PCT as an estrogen-antagonist alternative to aromatase inhibitors.
PubChem CID 5035 (free base). PK: Snyder 2000 (PMID:11006795) verbatim "the elimination half-life averages 32.5 hours." Occupancy SKIP — only verbatim value is an antagonist IC50 (1 nM, Fitzpatrick 1999 PMID:10465261), incompatible with the agonist model (see AUTHORING_GAPS). PK: THE WORST SINGLE ERROR FOUND IN THIS AUDIT, AND BOTH MISSING NUMBERS WERE VERBATIM IN THE ABSTRACT THE RECORD ALREADY CITED. With no volume and no bioavailability the solver substituted 35 L and 0.9 — for a drug the same sentence describes as having "absolute bioavailability is only 2%" — and the record was rendering a peak concentration roughly TWO THOUSAND NINE HUNDRED TIMES the real one. The citation states the pair outright: "Approximately 60% of a dose is absorbed; however, absolute bioavailability is only 2%. The volume of distribution is 2348 L/kg for a single oral dose of 30-150 mg, and the elimination half-life averages 32.5 hours." THE TWO NUMBERS MUST NOT BOTH BE STORED. That volume is an APPARENT one from oral dosing — it already contains the 2 percent — so pairing it with a stored bioavailability of 0.02 would divide by absorption twice and inflate exposure fifty-fold. The volume is stored at the seventy-kilogram reference with bioavailability pinned at unity, the same convention ethosuximide, levetiracetam and brompheniramine use. THE 60 PERCENT IS A CLASS-2 DONOR SITTING IN THE SAME SENTENCE and is deliberately not stored: it is FRACTIONAL ABSORPTION, not bioavailability, and the gap between them is this drug entire first-pass glucuronidation. The catalogue has no field for that distinction, which is a schema gap already logged.
Pharmacokinetics
- Oral — t½ 32.5 h · F 100% · Vd 164360 L
Sources: PMID:11006795