True half lives of esters

[climber]

Half the stuff on the net is double what the other half says...for example I've seen almost as much say that enanthate is 4 days and a lot says 10...Half says prop is 4.5 the other half says 2.... I've been doing this a long time but any help with sorting this out is appreciated

 

[ripriot]

This is the site I use. It seems like some people base it off how long androgen levels remain elevated for after initial administration. If you did that for enanthate it would be 3-5 days. But that way is not accurate for half life.

Testosterone Propionate

Testosterone Propionate | C22H32O3 | CID 5995 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety/hazards/toxicity information, supplier lists, and more.

pubchem.ncbi.nlm.nih.gov

Testosterone Enanthate

Testosterone Enanthate | C26H40O3 | CID 9416 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety/hazards/toxicity information, supplier lists, and more.

pubchem.ncbi.nlm.nih.gov

 

[M@NU]

i think it also has to do with the carrier.
thicker oils dissipate more slowly with results in a longer half life.
Oils like Mig or MCT dissipate very fast --> shorts half life.
atleast this is my thesis

 

[ripriot]

i think it also has to do with the carrier.
thicker oils dissipate more slowly with results in a longer half life.
Oils like Mig or MCT dissipate very fast --> shorts half life.
atleast this is my thesis

How much do you think MCT and MIG shorts half life? What about EO? It’s thinner then those and has oleic acid in it. How does that affect the method of free testosterone concentration will determine its half-life? No one uses castor oil or cotton seed oil anymore.

 

[climber]

Thanks for responding guys...even with thinner oils, the ester is supposed to offer a timed release, right? And maybe we'd see a 10 or 20% difference with diff oils, not a whopping 50%??

 

[emeric delczeg]

Half the stuff on the net is double what the other half says...for example I've seen almost as much say that enanthate is 4 days and a lot says 10...Half says prop is 4.5 the other half says 2.... I've been doing this a long time but any help with sorting this out is appreciated

The termination half life is 4.5 with Cyp and Ant, for Prop the termination half life is 0.8 days. Most of the gurus don`t know s.....t. MRT (Residence time) has longer half life than termination, that why the best way to inject less more frequent.

 

[emeric delczeg]

How much do you think MCT and MIG shorts half life? What about EO? It’s thinner then those and has oleic acid in it. How does that affect the method of free testosterone concentration will determine its half-life? No one uses castor oil or cotton seed oil anymore.

The oil source has nothing to do with half life.

 

[emeric delczeg]

Thanks for responding guys...even with thinner oils, the ester is supposed to offer a timed release, right? And maybe we'd see a 10 or 20% difference with diff oils, not a whopping 50%??

No.

 

[Alzadosghost]

Emeric is correct. It’s the ester not the oil that dictates half life. That’s the kind of bro science on the net that does NOT help anyone.

 

[M@NU]

Emeric is correct. It’s the ester not the oil that dictates half life. That’s the kind of bro science on the net that does NOT help anyone.

ok, that explains the different half-lives of nebido compared to other test u products

 

[M@NU]

Emeric is correct. It’s the ester not the oil that dictates half life. That’s the kind of bro science on the net that does NOT help anyone.

wikipedia with its fucking bro science

Testosterone undecanoate - Wikipedia

en.wikipedia.org

oh wait, there are footnotes? oh wait, there are even studies linked?
noway
doesnt help anyone

 

[Mufasa123]

Carrier oil would create a depot and affect "realized half life" or dissipation in body. Same with injecting into fat vs muscle or an area with low blood flow. My understanding is that you can get some very significant variability in absorbtion which would significantly affect the "realized half life" of any single injection and this has been medically documented as I think I reca seeing the data and variance in a half life study (note - not my field and memory isn't great anyway). Now once absorbed and in blood stream then it's purely ester. Nebiedo uses thick castor oil for slower depot is my understanding.

 

[M@NU]

Carrier oil would create a depot and affect "realized half life" or dissipation in body. Same with injecting into fat vs muscle or an area with low blood flow. My understanding is that you can get some very significant variability in absorbtion which would significantly affect the "realized half life" of any single injection and this has been medically documented as I think I reca seeing the data and variance in a half life study (note - not my field and memory isn't great anyway). Now once absorbed and in blood stream then it's purely ester. Nebiedo uses thick castor oil for slower depot is my understanding.

well, for us the "realized half life" as you call it should be the relevant thing.
I want to know how stable my levels are after injecting. Theoretically calculated half lives doesnt help, because the reality is as youve said: Thicker oils take longer to dissipate which "adds" to the half life.
Someone taking Nebido every 20 days will feel completely different as someone taking test U in MCT or Mig every 20 days and blood work will show a difference in levels

 

[Mufasa123]

well, for us the "realized half life" as you call it should be the relevant thing.
I want to know how stable my levels are after injecting. Theoretically calculated half lives doesnt help, because the reality is as youve said: Thicker oils take longer to dissipate which "adds" to the half life.
Someone taking Nebido every 20 days will feel completely different as someone taking test U in MCT or Mig every 20 days and blood work will show a difference in levels

Going further into my memory the raw data showed in some cases days of variance (cyp or enanthate) on individual IM injections of the same into the same muscle as they tested blood levels over the period of days post injection. Type II (user) probably can offer more here. My conclusion was not to sweat this shit or overly optimize. 1x per week for cyp/enanthate can work, 2x is better, beyond that heavy diminishing returns for blood levels but to ahead and spread as convenient for your cycle and other injections plus lifestyle. Not saying other indirect impacts may not be better, like mood or E2 etc, but straight up serum T peaks/valleys individual injections varied so much that meh.

 

[pickapeck]

I don't know. I know that straight from the pharmacy West Ward TC crashes to 250 ng/dL bby the end of the week whereas Sun is still at 700 ng/dL by the end of the week with the same supposed dose.

 

[Scorpyd]

Looking for

Type-IIx​

 

[Type-IIx]

Yes, so, as aggravating as this is for an answer: there is wide inter-individual variation in pharmacokinetics for these oil-based preparations and additional factors that impact the biological half-life. Factors affecting dissolution of the depot from vehicle & of the bolus from administration site include the oil (e.g., Sesame vs. Arachis), muscle (quicker in larger muscle), volume (oil), composition of surrounding tissue, rate of blood flow, osmotic pressure, esterase activity, lymphatic drainage, injection depth, pH and osmolarity of solution, exercise, physical activity, and systemic illness (that's everything I can personally think of).

It is impossible to do anything besides use the average (mean) data that's been published. I do have this all compiled for my use - there's a lot to it - I might publish it for public consumption at some point. If you want an idea of how much variation in the data there is you can refer to Peter Bond's Book on Steroids section on Pharmacokinetics (Chapter 3).

Practically, SteroidPlotter is still a useful tool! It simply uses the published half-lives to estimate the steady-state half-lives of these compounds. It's still what I usually use to initially plot out my cycles.

Sometimes a KISS approach is optimal given the impossibility of truly calculating precisely these things.

 

[Scorpyd]

^ makes sense to me thank you Type-IIx

 

[emeric delczeg]

Yes, so, as aggravating as this is for an answer: there is wide inter-individual variation in pharmacokinetics for these oil-based preparations and additional factors that impact the biological half-life. Factors affecting dissolution of the depot from vehicle & of the bolus from administration site include the oil (e.g., Sesame vs. Arachis), muscle (quicker in larger muscle), volume (oil), composition of surrounding tissue, rate of blood flow, osmotic pressure, esterase activity, lymphatic drainage, injection depth, pH and osmolarity of solution, exercise, physical activity, and systemic illness (that's everything I can personally think of).

It is impossible to do anything besides use the average (mean) data that's been published. I do have this all compiled for my use - there's a lot to it - I might publish it for public consumption at some point. If you want an idea of how much variation in the data there is you can refer to Peter Bond's Book on Steroids section on Pharmacokinetics (Chapter 3).

Practically, SteroidPlotter is still a useful tool! It simply uses the published half-lives to estimate the steady-state half-lives of these compounds. It's still what I usually use to initially plot out my cycles.

Sometimes a KISS approach is optimal given the impossibility of truly calculating precisely these things.

Do you mean the termination half life, not residence half life.

 

[emeric delczeg]

well, for us the "realized half life" as you call it should be the relevant thing.
I want to know how stable my levels are after injecting. Theoretically calculated half lives doesnt help, because the reality is as youve said: Thicker oils take longer to dissipate which "adds" to the half life.
Someone taking Nebido every 20 days will feel completely different as someone taking test U in MCT or Mig every 20 days and blood work will show a difference in levels

The Nebino`s termination half life is 25 days, and the residential half life is about 40 days.