T Nation

Ideal Arimidex Dosage on TRT?


I’m on TRT @ 250 mg of Test cypionate /week what would the ideal Armidex dosage?

I only have 1 mg pills.

Thinking about taking them E3D.



Normal responders might need 2.5 mg/week. Suggest 125mg T twice a week and 1mg Arimidex at time of T injections. If you crash, you are an over-responder and need to stop for 5-6 days and resume at 1/4th the suggested dose.

Taking both at same time twice a week has T and Arimidex levels roughly rising and falling together which works well.

You can dissolve Arimidex in vodka 1mg/ml and dispense by volume to get arbitrary dosing. Seek E2=22pg/ml on lab work.

Does not work well with injecting once a week!


KSman I’ve seen you recommended .25 arimidex EOD on some posts and your recommendation here of up to 2.5 mg/week. Is your recommendation varying with the total dose of T the individual is using, i.e. if 50 mg test cyp twice weekly, then a lower dose of arimidex than if 250 mg of test cyp as here?

Thank you.



Your serum T levels dictate anastrozole needs. Normal responders need ~ 1mg anastrozole for ever 100mg T ester. Your serum T levels are proportional to your T dosing.

Anastrozole is a competitive drug and there is a linear relationship for sane dosing.

A few guys are T hypermetabolizers who need ~3x T dosing and the above rule of thumb obviously would not apply.

E2 labs are needed to refine dosing.

If on T+anastrozole you get E2=30pg/ml and target is E2=22pg/ml, you would modify dose by a factor of current/target = 30/22. This same method would apply if E2 was low and the calculation would reduce the dose.

E2=22pg/ml seems optimal for: mood, energy, fat loss and patterns, libido etc. A few guys need higher E2 to feel right, seems like they are wired differently which is probably differences in gene expression and enzyme coding variations [which we all have].

There is no way to know in advance if one is:

  • needing more E2 than other guys
  • is a T hyper metabolizer
  • anastrozole over-responder
  • vulnerable to damage from 5-alpha reductase inhibitors [hair loss drugs] or other zeno-testosterones
  • freely converts DHEA–>E2 in the adrenals
  • SERMs not protecting nipples or resolving gyno
  • low dose hCG promoting high T–>E2 in the testes
  • feeling bad with hCG


What would you define a “crash” as ?

Having been on Test Cypionate 250mg/week for 12 weeks, blood work showed E2 @ 22pg/ml.

And I had never taken armidex prior to that. However, I have noticed that my nipples are a little puffy and hard.

Any recommendations ?


how did you manage to get prescribed such a high dose of test per week? my doc shot me down when i asked to be moved from 100 to 200… he said he would never prescribe such a high dose.
also im very curious to know how you are getting nipple issues when your e2 is at the perfect range level. maybe the AC is on too high? lol


That seems perfect.

Anastrozole dose needs to match serum T levels.
What are:
And why to I need to ask?
Please list all of your labs, not just sex hormones.

Inject twice a week and always do labs halfway between to avoid variations from lab timing. Was E2=22pg/ml at day 7? With peak T at day 2, E2 might be higher then.

I am wondering if you are a T hypermetabolizer.


Hi you sound really knowledgeable on this subject.

Was wondering if it is ok to ask you a few questions on trt and estrodial levels


@KSman So Is it better to take you arimedex the same day of your T injection or is it better to take the arimidex 24hrs after T injection???

If im taking 100mg of T but my injection protocol is 50mg of T twice per a week what should my Arimidex protocol be and when should I take the Arimidex???