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Anastrozole (Aromatase Inhibitor)
Description
What is Anastrozole 1 (Astera Labs)?
Astera Labs anastrozole in 1mg tablets, 50 to a sachet. The standard on-cycle aromatase inhibitor, and the one most likely to be dosed too high.
Also sold as Arimidex, Anastrozol or anastrozole.
Anastrozole is a non-steroidal aromatase inhibitor. It sits on the aromatase enzyme and blocks it competitively, which stops testosterone converting to estrogen. The binding is reversible, so the effect fades as it clears and estrogen comes back up.
Anastrozole 1 benefits
- Reliable, predictable estrogen control on cycle, the most widely used option here
- Long half-life, so every other day dosing holds levels steady
- Reversible binding, so the effect fades rather than persisting if you stop
- Well documented, with more accumulated user experience than the alternatives
- 1mg tablets, which split cleanly into the 0.5mg most protocols actually use
Anastrozole 1 dosage
- Common starting point
- 0.25 to 0.5mg every other day
- Higher end
- 1mg every other day
- Adjust from
- An estradiol blood test, not from symptoms
- Frequency
- Every other day
- Half-life
- About 46 hours
- Post-cycle therapy
- Do not use, switch to a SERM
Most people sit at a quarter to half a tablet every other day. Starting at a whole tablet because that is what the tablet is, is one of the commonest routes to crashed estrogen.
Adjust from a blood test. High and low estrogen produce almost identical symptoms.
Package content
- Tablets
- 50 per sachet
- Strength
- 1mg anastrozole per tablet
- Anastrozole per sachet
- 50mg
- Half-life
- About 46 hours
- Brand
- Astera Labs
At 0.5mg 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 Anastrozole 1 for?
Anyone running a compound that aromatises whose bloodwork says estrogen is climbing.
ARIMIMED 1 is the same 1mg, the same 50 tablets, at the same price from Deus Medical. Choose on packaging alone. If you are also running tamoxifen, exemestane is the better choice.
How to use Anastrozole 1
Swallow with water, every other day at the same time. Split tablets with a pill cutter for the quarter and half doses most protocols use. 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.
How do I dose a 1mg tablet when I need 0.5mg?
Split it. 1mg every other day is a high dose for most people and 0.25 to 0.5mg every other day is where the majority actually sit, so halving or quartering tablets is normal with this compound.
A pill cutter makes it consistent. Starting at a whole tablet because that is what the tablet is, is one of the commonest routes to crashed estrogen.
Anastrozole or exemestane?
Anastrozole is the default and the better documented of the two. Exemestane has three real advantages: it binds irreversibly so there is no estrogen rebound when you stop, it treats cholesterol more kindly, and it does not interact with tamoxifen.
If you are running a SERM alongside, or you know you react badly to rebound, exemestane is the better choice. Otherwise anastrozole does the job.
All products are supplied exclusively for research and evaluation purposes and are not positioned as medical treatments or health solutions.
