At a glance
Effects
- Lowers estrogen (estradiol): Markedly suppresses circulating estradiol by blocking aromatase.[2][3]
- Slows estrogen-dependent tumor growth: Reduces estrogen available to hormone receptor-positive breast cancer cells.[1][3]
- Controls estrogen side effects in men (off-label): Used with TRT to reduce gynecomastia, water retention and mood changes from high estradiol.[6][9]
- Modestly raises testosterone in men: By reducing conversion to estrogen, it can nudge testosterone upward.[8][6]
Non-steroidal aromatase inhibitor (not an AAS)
~50 hours (≈2 days)
Oral tablet
Steady state ~7 days
Lowers BMD with chronic use
About Anastrozole
Every point here is drawn from public medical and harm-reduction sources. A bracketed number after a claim — like [1]— is a reference: tap it to open the exact source it's based on (numbered list at the bottom). It is not a rating or score. Educational information, not medical advice.
Product specifics
- Est. delivery
- 3–7 business days · EU tracked
Product details as stated by the vendor (claims, not independently verified). Delivery is our standard EU estimate.
What it is
Anastrozole is a non-steroidal aromatase inhibitor — NOT an anabolic-androgenic steroid, despite the vendor classification.[1][3] It is FDA-approved to treat hormone receptor-positive breast cancer in postmenopausal women, and is used off-label by men to control estrogen, e.g. to manage estrogen-related side effects on testosterone therapy.[1][6][9]
How it works
It blocks the aromatase enzyme, which converts androgens such as testosterone and androstenedione into estrogen, thereby lowering circulating estradiol.[3][7][8] In postmenopausal women it can inhibit aromatase activity by more than 96% and reduce plasma estrogen by over 78%.[2] In men on testosterone therapy it is used to keep estradiol from rising too high, since some testosterone naturally converts to estrogen.[6][9] It is selective — it lowers estradiol without affecting adrenal corticosteroid or aldosterone formation.[8]
Risks & side effects
Most important: By lowering estrogen, anastrozole accelerates bone mineral loss and raises the risk of osteoporosis and fractures with longer-term use — and in people with pre-existing ischemic heart disease it has been linked to more cardiovascular events.[5][7][8] Estrogen is needed for bone, cardiovascular and cognitive health, so over-suppression (especially in men) can do more harm than good.[8][9]
Common
Serious
Safety & harm reduction
- Estrogen-containing therapies (HRT, hormonal contraceptives) negate its effect — avoid[1]
- Tamoxifen may reduce anastrozole plasma levels[1]
- CYP3A4 inducers (e.g. rifampin) can lower anastrozole levels; CYP3A4 inhibitors can raise them[1]
- Alcohol and tobacco may worsen side effects / cardiovascular risk[1]
- Use the lowest effective dose for the shortest necessary duration, especially off-label in men[7]
- Support bone health: weight-bearing exercise, vitamin D/calcium, and bisphosphonates where indicated[7]
- Avoid over-suppressing estrogen — men need some estradiol for bone, cardiovascular and cognitive health[8][9]
- Titrate to bloodwork rather than fixed dosing[9]
Dosage context
Commonly-reported, not a prescription. The FDA-approved dose for breast cancer is 1 mg orally once daily.[4] Off-label in men on testosterone therapy, clinicians have reported much lower doses — e.g. roughly 0.5 mg one to three times weekly, titrated to bloodwork — with the principle of the lowest effective dose for the shortest time.[7][9] Importantly, the most rigorous study found only about 3% of men on TRT actually needed an aromatase inhibitor, and guidelines do not recommend routine use.[6] These figures are context only — dosing must be individualised and guided by a clinician and lab monitoring.
Sources
- 1.MedlinePlus — Anastrozole
- 2.PMC — Anastrozole aromatase inhibition (case study)
- 3.NCI — Anastrozole
- 4.PubMed — Anastrozole pharmacology (terminal half-life 50h, 1mg daily)
- 5.DailyMed — Anastrozole label (warnings)
- 6.DrOracle — AI dosing/monitoring in men on TRT
- 7.NHS — Side effects of anastrozole
- 8.Drugs.com — What anastrozole does to your body
- 9.DrOracle — Logic of anastrozole with TRT (dose/monitoring)
- 10.PMC — Anastrozole-associated ocular complications
This information is provided for educational and harm-reduction purposes only. It is not medical advice. These substances can carry serious health risks; effects and safe use vary by individual. Consult a qualified healthcare professional before use. Legal status varies by country — it is your responsibility to know your local law. We do not encourage misuse.
Other options for Anastrozole· 11 offers
Same compound from different labs/brands and pack sizes. Tap a row to switch brand — the price and buy button update instantly.
This compound comes in different forms (e.g. injectable vs oral vs topical). Cost per mg is only comparable within the same form.
| Brand | Form | Strength | Pack | Price | Per mg |
|---|---|---|---|---|---|
Royal Pharma | blister-pack | 1 mg/tab | 30 tab | 34,90 € | €1.163/mg |
Generic | blister-pack | 1 mg/tab | 50 tab | 48,90 € | ★€0.978/mg |
Generic | — | — | 49,90 € | — | |
Intex Pharma | — | — | 52,90 € | — | |
Generic | blister-pack | 0.5 mg/tab | 50 tab | 64,90 € | €2.596/mg |
Generic | vial | 3 mg/ml | 50 ml | 69,90 € | €0.466/mg |
Hemi Pharma | blister-pack | 1 mg/tab | 60 tab | 89,90 € | €1.498/mg |
Generic | blister-pack | 1 mg/tab | 50 tab | 89,90 € | €1.798/mg |
GenericSelected | oral-liquid | 3 mg/ml | 100 ml | 169,99 € | €0.567/mg |
Generic | blister-pack | 1 mg/tab | 28 tab | 209,99 € | €7.500/mg |
Generic | blister-pack | 1 mg/tab | 50 tab | 219,99 € | €4.400/mg |