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Cycle support / Aromatase inhibitors

4 In the index

Letrozole LETRO

An FDA-approved breast cancer drug that lowers estrogen, also used off-label to help with ovulation and to control estrogen in steroid users. Its cancer and fertility uses are strongly backed by research, while over-suppressing estrogen this way can hurt joints and cholesterol levels.

Also known as Femara, Letrozol, CGS 20267, 7LKK855W8I, CHEBI:6413, letrozolum, Letrozole Tablets

Effects Hormonal
Routes Oral
Legal status Prescription drug
WADA Banned at all times

3D Molecular Structure of C17H11N5

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  • Carbon
  • Hydrogen
  • Nitrogen

Chemistry

Formula
C17H11N5
Molar mass
285.30
CAS
112809-51-5
PubChem CID
3902
IUPAC name
4-[(4-cyanophenyl)-(1,2,4-triazol-1-yl)methyl]benzonitrile
InChIKey
HPJKCIUCZWXJDR-UHFFFAOYSA-N

Reported dosing

User-reported

What has been reported in the literature and by users. This is a record of what is done, not a recommendation.

Typical dose 2.5 mg/day
Reported range 2.5 mg/day (standard); off-label bodybuilding doses often much lower and intermittent (e.g., 0.5-1.25 mg every few days)
Route Oral
Frequency Once daily, or intermittently (off-label use)
Duration Chronic (oncology) or cycle-length (off-label bodybuilding use)

FDA-approved aromatase inhibitor (Femara) for breast cancer, one of the most potent in its class; off-label bodybuilding use risks over-suppressing estrogen, with negative effects on lipids, joints, and bone.

Where this comes from FDA prescribing information; off-label user-reported dosing

There is no approved human dosing for this compound. The figures above are what users and vendors report, not what has been established as safe or effective. Treat them as a record of what is done, not as guidance.