T Nation

Half Life of AI Compared to Test E

Ok during my last 2-cycles - 6 weeks Test E at 250mg 2 x per weeks and 0.45mg Anastrozole EOD I have noticed that sex drive increases dramatically through weeks - 7, 8, 9 - as Test levels are falling.

I assume that this must be related to estrogen levels either rising or falling? My question is on those doses what is falling the quickest over the last three weeks test or AI. Knowing this will enable me on my next cycle to increase or decrease AI dose accordingly.

Thanks

So let me understand correctly. You take 6 weeks of test e and then stop it completely? Then you take the adex EOD during when weeks 1-6 or 1-9? Its very true if E is too low or too high it can affect sex drive

Anastrozole typically clears somewhat faster than testosterone enanthate.

As there’s individual variation, there might be some individuals for whom the clearance is about the same. But based on average values in the literature, anastrozole typically has a shorter half-life.

[quote]Bill Roberts wrote:
Anastrozole typically clears somewhat faster than testosterone enanthate.

As there’s individual variation, there might be some individuals for whom the clearance is about the same. But based on average values in the literature, anastrozole typically has a shorter half-life.[/quote]

Ok thanks - will lower my AI dose a touch next time and see what happens

[quote]saps wrote:
So let me understand correctly. You take 6 weeks of test e and then stop it completely? Then you take the adex EOD during when weeks 1-6 or 1-9? Its very true if E is too low or too high it can affect sex drive[/quote]

6 weeks of test e, with 6 weeks of AI. Stop both dead - while I wait for test E to clear my system

[quote]saps wrote:
So let me understand correctly. You take 6 weeks of test e and then stop it completely? Then you take the adex EOD during when weeks 1-6 or 1-9? Its very true if E is too low or too high it can affect sex drive[/quote]

Week 1-6 test and AI. Week 7-9 nothing at all. Start my PCT end of week 9.

Cymru,

How was your libido during the cycle?
Any signs of high estradiol while on, or were there signs indicating it was low?

Bill, saps, or anyone with knowledge on this:

What is the approx. half-life of test enanthate?
What is the approx. half-life of anastrozole? Of letro?

I ask all this because I am in a similar situation. Although i’m on HRT, my libido seems higher when test enanthate and letro are at their lowest, just before my next shot (50 mg test every 3-1/2 days, 1 drop letro every morning).

The value I use as an estimate for the half-life of testosterone enanthate is 5 days, though there is a literature value for 4 days.

A literature value for the half-life of anastrozole is 50 hours, which is about 2 days.

For letrozole, also about 2 days or a little over.

Individuals do vary.

[quote]poophead wrote:
Cymru,

How was your libido during the cycle?
Any signs of high estradiol while on, or were there signs indicating it was low?

Bill, saps, or anyone with knowledge on this:

What is the approx. half-life of test enanthate?
What is the approx. half-life of anastrozole? Of letro?

I ask all this because I am in a similar situation. Although i’m on HRT, my libido seems higher when test enanthate and letro are at their lowest, just before my next shot (50 mg test every 3-1/2 days, 1 drop letro every morning).[/quote]

Libido was good on cycle - it just increased dramatically during weeks after cycle which makes me think there was an estrogen issue

[quote]Cymru wrote:

[quote]poophead wrote:
Cymru,

How was your libido during the cycle?
Any signs of high estradiol while on, or were there signs indicating it was low?

Bill, saps, or anyone with knowledge on this:

What is the approx. half-life of test enanthate?
What is the approx. half-life of anastrozole? Of letro?

I ask all this because I am in a similar situation. Although i’m on HRT, my libido seems higher when test enanthate and letro are at their lowest, just before my next shot (50 mg test every 3-1/2 days, 1 drop letro every morning).[/quote]

Libido was good on cycle - it just increased dramatically during weeks after cycle which makes me think there was an estrogen issue
[/quote]
Absolutely agree. Given what Bill said about half lifes [I completely agree] in your case you probably were too high on your adex and that drove your estrogen too low so with the shorter half life of adex once you stopped it, it cleared faster than the test e and your body adjusted better