I'm a new to this entire scene, started with levels of around 320, age 40, doctor started me on 100mg once a week. Curious on what type of levels I should expect to see from this?
Thanks
Very informative response, thanks so much. So over the next 6 to 8 weeks I could expect to see an improvement, is that due to the T progressively increasing? I asked my doctor about 2x a week, he suggested we stay at one a week to see how I feel post 6 weeks
Also, would you say 100mg is a good starting place? I was told it's Test Cypionate
Im on 100mg once a week my levels 2 days after are 1050 4 day’s after are 850 and 7 days after are 500I'm a new to this entire scene, started with levels of around 320, age 40, doctor started me on 100mg once a week. Curious on what type of levels I should expect to see from this?
Thanks
It's interesting to get data like this to see what kind of apparent half-life it has. In your case it is 4.9 days, with a predicted peak testosterone around 1,300-1,400 ng/dL.Im on 100mg once a week my levels 2 days after are 1050 4 day’s after are 850 and 7 days after are 500
It's interesting to get data like this to see what kind of apparent half-life it has. In your case it is 4.9 days, with a predicted peak testosterone around 1,300-1,400 ng/dL.
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Maybe you can explain this possible discrepancy. Assume first order absorption and first order utilization, which results in the usual bi-exponential curve. The problem is that with the typical measured parameters the time to achieve peak level should be fairly insensitive to the absorption constant, because it's so much longer than the consumption constant. For example, the half-life of testosterone in serum is on the order of minutes, while the half-life of testosterone cypionate is more like five days. These values result in a very early post-injection peak, at most a few hours. Anecdotally I do see this fast rise with testosterone propionate. But the situation with cypionate is less clear—your data are showing a couple days to peak, which seems long.Cool data, thanks guys. I had been using a zero compartment model (was being lazy) but have moved over to a one-compartment model with first order absorption and linear elimination based on this work:
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Maybe you can explain this possible discrepancy. Assume first order absorption and first order utilization, which results in the usual bi-exponential curve. The problem is that with the typical measured parameters the time to achieve peak level should be fairly insensitive to the absorption constant, because it's so much longer than the consumption constant. For example, the half-life of testosterone in serum is on the order of minutes, while the half-life of testosterone cypionate is more like five days. These values result in a very early post-injection peak, at most a few hours. Anecdotally I do see this fast rise with testosterone propionate. But the situation with cypionate is less clear—your data are showing a couple days to peak, which seems long.
Indeed, the earlier Nieschlag data, also using hypogonadal men, shows a peak for enanthate that's under 14 hours....
I get an apparent elimination half life of 6.8 days, apparent absorption half life of 5.3 hr and calculated tmax of 27 hours. So quite a diversity among the literature data. ...
Indeed, the earlier Nieschlag data, also using hypogonadal men, shows a peak for enanthate that's under 14 hours.
Assuming the literature is correct in saying the half-life of testosterone in plasma is around 10-100 minutes, what else is going on to delay time to peak serum levels?
So my takeaway is the empirically-fit half lives for "absorption" and "elimination" are most likely co-variant and as you state much longer than the actual elimination half life of testosterone in the body. You've got the surface area to volume ratio of the oily depot, hydrolysis of the ester, sub-Q vs IM, whether the patient pushes on the injection site with their finger after injection (changes the surface area to volume ratio).
Indeed, the earlier Nieschlag data, also using hypogonadal men, shows a peak for enanthate that's under 14 hours.
Assuming the literature is correct in saying the half-life of testosterone in plasma is around 10-100 minutes, what else is going on to delay time to peak serum levels?
ME INTERSA, Ejemplo... mi análisis dice 450 n/dl.... cuanta enantato de testosterona debería inyectarme, para tener 880 ng/dl. ????Just as an academic exercise it's interesting to make a rough prediction of the average serum testosterone levels an average young man would achieve with 100 mg testosterone cypionate per week. Here are the assumptions:
We'll just use 6.5 mg natural T production resulting in 650 ng/dL TT. So weekly natural production is 45.5 mg T, which is the amount contained in 65 mg T cypionate. We convert from peak to average serum testosterone by multiplying by 80%: 520 ng/dL. With unchanging albumin and SHBG we'll assume that total testosterone is linear with dose. Therefore:
- Average natural testosterone production: 6-7 mg
- Average peak testosterone 600-700 ng/dL
- Diurnal variation off of peak: 40%
- No change in albumin or SHBG
TT(avg-100mg/w) = 520 ng/dL * 100 mg TC / 65 mg TC = 800 ng/dL
This is the predicted average serum level, meaning it's what would be measured if the guy were injecting frequently, e.g. daily and maybe even EOD. But suppose he starts out with injections once a week and has typical absorption for cypionate, meaning a 5-day half-life. Then he measures a trough level of about 450 ng/dL. We see this kind of thing all the time. Guys measure a lowish trough like this and want to greatly increase the dose. But the post-injection peak in testosterone is ignored. In this example it is more like 1,150 ng/dL.
No sería raro en un caso como este que la dosis se incrementara en un 50% para elevar la medición mínima a niveles de hombres jóvenes sanos de 600-700 ng / dL. No se ve que la testosterona sérica promedio salta a 1.200 ng / dL y el pico se eleva a más de 1.700. Luego, la gente se sorprende cuando aparecen todos los efectos secundarios: HCT, problemas de E2, problemas de DHT, etc.
ME INTERSA, Ejemplo... mi análisis dice 450 n/dl.... cuanta enantato de testosterona debería inyectarme, para tener 880 ng/dl. ????
It's not possible to know without more information. If you were the theoretical "average young man" discussed in my example then it would take 107 mg of testosterone enanthate. But you are a unique individual, which means that only by injecting testosterone and getting lab work will you find your response to various doses.I AM INTERESTED, Example ... my analysis says 450 n / dl .... how much testosterone enanthate should I inject, to have 880 ng / dl. ????