Yes study in first link used T enant and a total of 14 subjects. Half life in hypogonadal and eugonadal subjects was a bit over 4 days. 14 subjects is not a huge number, but it already gives a quite confident assessment on the PK behavior.
Interesting in this and the second study is how fast LH drops and also how prolactin increases.
Second link uses also T enant and only 5 subjects, that’s correct. Half life can be easily read out from the PK curve (C half of totalT - look at the units). It’s about about 4 days.
The third one used T cyp in 11 subjects. Unfortunately it’s not freely accessible and you need an institutional subscription to access. The determined half life is around 5 days.
The fourth study used T enant and 15 cynomolgus monkeys . It also needs an institutional subscription to access. Cyn monkeys is a well established model organism due to the highly comparable PK behavior to the human system. Establish half life was 5 days.
The last link presents the data of a comparative study between T enant and cyp (6 subjects each). It’s shows that the esters are highly comparable in terms of PK and the half life as seen from the profiles (C half) is about 4.5 days.
While I appreciate the input it has nothing to do with my original question of whether injection is better than gel for the purposes of what the provided link is talking about. Does anyone concur with the article? Have you seen any other studies supporting this claim?
There are some guys who do better on topicals and most guys do better on injection, the best method is going to vary based on the individual, but injections provides more lean muscle mass.
Some men report a higher libido on topicals versus injections. If you’re looking for a concrete answer, you may be disappointed because it’s going to depend on the individual.
There is a guy on another forum who didn’t do well on injection at all, never felt good for years, but tropicals is the only thing that worked for him.
So if you’re one of those guy with high libido on topicals, but higher muscle mass on injections, which is better, injections or topicals?
This is a question you’re going to have to answer.
I have not seen any particular scientific evidence to indicate that injections work better than gels though there seems to be a lot of anecdotal evidence or maybe just bro-science in the forums to indicate that. Some have said that the absorption of the gel can vary over time and they don’t absorb it well or develop skin reactions. I use gel and it works great. It sounds like you absorb it just fine so that isn’t an issue. Cost can certainly be a factor. If your insurance is paying for it then that might not be a big deal (I pay $10 a month co-pay) but then you’re stuck using a doctor in your insurance network who might not be willing to prescribe optimal dosages. My doc, for example, doesn’t want to go past 75mg/day 1% gel. If I want to try higher I’ll need to find another doc but to be honest, I don’t have any particular complaint that I could use to justify a higher dose. All of my low-T symptoms resolved at 75mg. Life is good. Most of those T clinics don’t seem to take insurance so then the injections are much more cost effective than gel. I find the gel so convenient that it would be hard to switch to poking myself. It’s just become part of my morning routine - s**t, shower, shave, brush my teeth, apply gel. Wait 5 minutes, put my shirt on and go about my business.
Yep, sad to say but the bro-science and anecdotes seem to be ahead of actual science in TRT much as in that other related area over in Pharma. Some of the studies are so poorly designed I don’t know how they got approved and funded.
Some organization wanted something brought to light, even if it’s not true, like TRT “causes” heart attacks which forced the FDA to put out a warning. Later the experts are saying TRT doesn’t “cause” prostate cancer or heart attacks and cardiovascular problems.
Now the oral testosterone does cause cardiovascular problems, but not the injectable and topicals. You have to weed through all the poor studies to get the facts, this is why a lot of docs are not even going to get their feet wet in the world of TRT.
It’s just easier to tell them levels are normal so they leave and are someone else’s problem. All of the randomized placebo controlled studies done by the pharmaceutical companies show mostly benefit and that the untreated low T men health outcome is grim.
Gels is actually the most widely prescribed form of TRT and for most men they work just fine.
Set aside the bro science bla bla there is some good scientific data available that indicates two drawbacks of gels:
gels are associated with a higher incidence of cardiovascular events. Thats probably due to the high conversion of T into DHT in the skin (which may also explain the high libido on gels)
the T can quite easily be transferred to other persons, eg wife or kids. Studies have shown that a remarkable amount of T is passed onto the partner during intercourse if the residual T on the skin hasnt been removed by showering. Studies have also shown that some T was passed on even when wearing a T shirt. I have kids and that was reason enough for me to switch to the injectable form
This isn’t what the countless clinicians are saying who have tons of clients, in fact they don’t bother with gels anymore unless the guy is terrified of needles. I see guys all the time claiming there levels are no higher than pre-TRT right here on T-Nation and it’s not the minority either.
I doubt there are members here willing to make that claim on any forum, in fact gels only work for 38% of men and some of those stop absorbing after awhile and eventually end up on injections or T scrotal cream.
Afterall the T cream was created out of a need for more reliable, better absorbed product.
Why else would we need T scrotal cream if gels are so effective?