Aromasin vs Tamoxifen
Aromasin and Tamoxifen are compared here on the things that actually differ between them: what class each belongs to, what each acts on, how each is supplied and what each costs per milligram. Where the registry has no figure for one of them the row is left out rather than filled in.
Side by side
| Aromasin | Tamoxifen | |
|---|---|---|
| Class | Steroidal (suicidal) aromatase inhibitor | Selective oestrogen receptor modulator (SERM) |
| Acts on | A steroidal aromatase inhibitor that binds the enzyme irreversibly, so activity returns only as new enzyme is synthesised. This distinguishes it from the reversible non-steroidal inhibitors. | A triphenylethylene SERM: antagonist at breast tissue oestrogen receptors, agonist at others including bone and liver. Blocks hypothalamic oestrogen negative feedback, raising LH and FSH output. |
| Supplied as | Oral tablet. | Oral tablet. |
| Half-life | Approximately 24 hours, though the irreversible mechanism outlasts the plasma half-life. | Long, approximately 5 to 7 days, with an active metabolite longer still. |
| Storage | Cool, dry, dark. | Cool, dry, dark. |
| Listings | 1 | 2 |
| Price from | £35 | £22 |
What actually differs
The clearest difference is class: Aromasin is a steroidal (suicidal) aromatase inhibitor, Tamoxifen is a selective oestrogen receptor modulator (SERM). Half-life differs as well: Approximately 24 hours, though the irreversible mechanism outlasts the plasma half-life for Aromasin against Long, approximately 5 to 7 days, with an active metabolite longer still for Tamoxifen.
What is Aromasin?
Aromasin is a steroidal (suicidal) aromatase inhibitor. A steroidal aromatase inhibitor that binds the enzyme irreversibly, so activity returns only as new enzyme is synthesised. This distinguishes it from the reversible non-steroidal inhibitors.
What is Tamoxifen?
Tamoxifen is a selective oestrogen receptor modulator (SERM). A triphenylethylene SERM: antagonist at breast tissue oestrogen receptors, agonist at others including bone and liver. Blocks hypothalamic oestrogen negative feedback, raising LH and FSH output.
Quanta Pharma Aromasinout of stock£35
Tamoxifen - PHARMAin stock£22- Quanta Pharma Tamoxifen 20mgout of stock£25
Availability checked 2026-09-09. The product page carries live stock.