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Exemestane 25 mg
Description
What is Exemestane 25 (Astera Labs)?
Astera Labs exemestane in 25mg tablets, 50 to a sachet. The aromatase inhibitor that binds permanently, so stopping it does not rebound estrogen.
Also sold as Aromasin, Exemestan or exemestane.
Exemestane is a steroidal aromatase inhibitor and it works differently from the others here. Rather than competing for the enzyme, it binds to it permanently and takes it out of service, so your body has to build new aromatase to recover. That is why it is described as a suicidal inhibitor, and it is why stopping it does not produce the estrogen rebound the non-steroidal ones can.
Exemestane 25 benefits
- Binds aromatase irreversibly, so there is no estrogen rebound when you stop
- Kinder to cholesterol than anastrozole or letrozole
- No interaction with tamoxifen, so it is the right aromatase inhibitor to pair with a SERM
- Mildly androgenic in its own right rather than purely an anti-estrogen
- 25mg tablets, which is a standard dose with nothing to split
Exemestane 25 dosage
- Common starting point
- 12.5mg every other day, half a tablet
- Standard
- 25mg every other day
- Higher end
- 25mg daily
- Adjust from
- An estradiol blood test, not from symptoms
- Half-life
- About 24 hours
- Post-cycle therapy
- Do not use, switch to a SERM
12.5mg every other day is a sensible starting point and plenty of people never need more.
Adjust from a blood test. High and low estrogen produce almost identical symptoms, so dosing by feel usually means overshooting.
Package content
- Tablets
- 50 per sachet
- Strength
- 25mg exemestane per tablet
- Exemestane per sachet
- 1250mg
- Half-life
- About 24 hours
- Brand
- Astera Labs
At 12.5mg every other day one sachet covers around 200 days.
Store below 30°C. Protect from light. Do not freeze. Keep out of reach of children.
Who is Exemestane 25 for?
Anyone who wants estrogen control without rebound, anyone running tamoxifen alongside, and anyone whose lipids are already a concern.
AROMAMED 25 is the same 25mg strength from Deus Medical in a boxed blister.
How to use Exemestane 25
Swallow with water after food, which improves absorption noticeably with this compound. Every other day is the usual schedule. Stop it when the cycle ends.
Frequently asked questions
How do I know if my estrogen is too low?
You largely cannot tell from symptoms, which is the whole problem. Low estrogen and high estrogen both produce low libido, erectile difficulty, poor mood and general flatness.
Aching or clicking joints and completely dry skin lean toward low, and puffiness and sensitive nipples lean toward high, but neither is reliable. This is the one thing in a cycle you genuinely should not guess at. Test estradiol.
Do I even need one?
Not automatically, and starting one because a cycle plan listed it is how a lot of people end up crashed. Compounds that do not aromatise, such as trenbolone, drostanolone, stanozolol or oxandrolone, produce no estrogen at all.
Even on testosterone, plenty of people at moderate doses never need one. Test estradiol a few weeks in and decide from the number rather than from the plan.
Should I use it during PCT?
No. Post-cycle recovery depends on estrogen being present, because the feedback loop that restarts your own production runs through it. Suppressing estrogen at that point works directly against the goal.
Use a SERM such as tamoxifen or clomiphene for post-cycle therapy and stop the aromatase inhibitor when the cycle ends.
What does suicidal inhibitor mean?
It means exemestane binds to the aromatase enzyme permanently rather than competing with testosterone for it. That enzyme is then out of action for good, and your body has to synthesise new aromatase to restore capacity.
The practical consequence is that there is no rebound. With anastrozole or letrozole, stopping releases the enzyme and estrogen can spike back up. With exemestane it comes back gradually as new enzyme is made.
Why is it the better one to run with tamoxifen?
Because tamoxifen lowers anastrozole blood levels by a meaningful margin, so that pairing gives you less aromatase inhibition than the dose implies. Exemestane does not have that interaction.
If you are treating gyno with a SERM while still controlling estrogen on cycle, exemestane is the aromatase inhibitor that will actually do what you are dosing it to do.
All products are supplied exclusively for research and evaluation purposes and are not positioned as medical treatments or health solutions.
