Explore Tamoxifen dosage trends, reconstitution volumes, and vial size patterns from anonymized WPA peptide calculator data.
Tamoxifen is an estrogen-blocking drug (a SERM) approved as Nolvadex for breast cancer, sourced in research for estrogen-balance and post-cycle studies. It ships as tablets or a research-grade powder.
Tamoxifen is a prodrug; the parent compound and its active metabolites (4-hydroxytamoxifen and endoxifen, both produced primarily by CYP2D6) bind the estrogen receptor and act as antagonists in breast tissue while acting as partial agonists in bone, endometrium, liver, and the cardiovascular system — the defining "selective" character of the SERM class. In ER-positive breast cancer, the antagonist effect at the breast-tissue estrogen receptor blocks the estrogen-driven proliferation that those tumours depend on. The partial-agonist effects in endometrium underpin the small but real increased risk of endometrial cancer that long-term tamoxifen use carries.[3]
NSABP B-14 (Fisher et al., JNCI 1996) established the recurrence and mortality benefit of adjuvant tamoxifen in node-negative ER-positive breast cancer.[4] The EBCTCG meta-analyses (Lancet 2011) confirmed that 5 years of adjuvant tamoxifen reduces breast-cancer recurrence by ~50% and breast-cancer mortality by ~30% in ER-positive disease, with effects persisting beyond 15 years.[5] ATLAS and aTTom established that 10 years of adjuvant therapy outperforms 5 years.[6] NSABP P-1 (Fisher et al., JNCI 1998) and IBIS-I (Cuzick et al., Lancet 2002) established the risk-reduction indication in high-risk women.[7] Off-label use as part of male anabolic-steroid post-cycle therapy and for gynecomastia management is widespread but not characterised by Phase 3 data.
FDA-approved for the treatment and adjuvant treatment of estrogen-receptor-positive breast cancer, ductal carcinoma in situ, breast-cancer risk reduction in high-risk women, and McCune-Albright syndrome. Off-label use for gynecomastia, fertility, and anabolic-steroid PCT is widespread but not approved. Research-grade material elsewhere.
Tamoxifen has a reported half-life of ~5–7 days (longer for active metabolite). The pharmacokinetic reference models an interval of once daily; this is not a measured community cadence or a dosing recommendation. A multi-day half-life means tamoxifen builds up over several weeks to steady state, so missing a single daily dose barely moves overall levels. Its active metabolite persists even longer. Pharmacokinetic source: FDA label (Nolvadex). It is catalogued under Other Peptides on WPA.
The WPA community has not yet logged enough Tamoxifen calculator sessions to publish dose, vial size, or bacteriostatic water distributions for it. This page therefore covers what is known about the compound itself; the usage charts fill in as researchers run the calculator.
These figures come from anonymized WPA peptide calculator sessions, not verified administrations or unique people. Separate modal inputs do not establish a joint protocol. They are community input statistics — not dosing recommendations, and not medical advice.
These figures come from anonymized WPA peptide calculator sessions.
All figures shown are aggregated from anonymized calculator inputs and are provided strictly for independent laboratory research and educational purposes. They are community usage statistics — not dosing recommendations, and not medical advice.