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Testosterone Undecanoate

B

Bluenoser

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SB Labs

Hello, I am new to the site, I have a question that someone may be able to help me with.​


I have been taking 250mg of Testosterone Cypionate injections weekly for about 3 years without a break, however due to a new job which I will start in roughly a month, I'm faced with not being able to take anything for 21 days at a time, so I've been looking at a solution, I've come across an alternative with a much longer half life "Testosterone Undecanoate", my question is would I be able to inject this @750mg every three weeks instead of my regular weekly Testosterone Cypionate without there being a major hormone change?​

 
  • Initial Dose: A first dose of 1000 mg is administered.
  • Second Dose: A second "loading dose" of 1000 mg is given after six weeks.
  • Maintenance Phase: After the second loading dose, injections are usually spaced at 10 to 14 week intervals, depending on the patient's individual response and testosterone levels.
 
javman said:
  • Initial Dose: A first dose of 1000 mg is administered.
  • Second Dose: A second "loading dose" of 1000 mg is given after six weeks.
  • Maintenance Phase: After the second loading dose, injections are usually spaced at 10 to 14 week intervals, depending on the patient's individual response and testosterone levels.
Click to expand...
This is for the Script drug Nebido...... Trust me... that 4ml amp with a gram in it fuckin hurts to pin!!!!
If wanting to do HRT Id find a UGL that carries it and do less volume. ALWAYS get blood work to see
what dose jives with you.
 
I've used UG and so has my friend with excellent results, less pinning and steadier levels and no PIP!
 
Thanks for the information, I guess I'll have to try it out and see how it goes, if I don't my test levels would be very low after three weeks of nothing.
 
I did an experiment with taking only 200mg for several weeks and stopped for a couple pulled labs and my T levels were close to 800. My buddy did the loading phase one and started the once a month dose of 400mg and his leveled off at 1900 at that dose.
 
Those results sound very encouraging, I'm glad this option is out there, I'll have to just take and go, do the lab work once I get back, I won't be able to check until I get back after the hitch.
 
I would take 600-750mg depending on which on have and you should be fine while you are on the road for that time frame you mentioned!
 
Okay that's what I'll do, it's a demanding job + the gym afterwards, trying to find the best ways not to disrupt my routine too much, thank you so much your advice.
 
You'll have a bit higher variation, but it's nothing major. And beats the alternative of nothing, here's the math curtesy of grok ai:

Testosterone Cypionate vs. Undecanoate: Blood Level Comparison​

AspectTestosterone Cypionate (250 mg/week)Testosterone Undecanoate (925 mg/26 days)
Half-Life~7–8 days~20–33 days (avg. 26 days)
Dosing Schedule250 mg every 7 days925 mg every 26 days (~250 mg/week)
Peak Level (nmol/L)~27 nmol/L (day 1–2)~24 nmol/L (day 7–10)
Trough Level (nmol/L)~15 nmol/L (day 7)~11 nmol/L (day 26)
Peak-Trough Swing~12 nmol/L (~44% variation)~13 nmol/L (~54% variation)
StabilityTighter control, higher troughsLarger relative swings, low-normal troughs
Use CaseTRT, bodybuilding (flexible)TRT (less frequent injections)
DrawbacksWeekly injectionsLow-normal troughs, slower adjustments
Conclusion: Testosterone cypionate (250 mg/week, every 7 days) is slightly more stable than testosterone undecanoate (925 mg every 26 days) due to smaller relative swings (44% vs. 54%) and higher troughs (15 vs. 11 nmol/L), staying comfortably within the physiological range (10–30 nmol/L).
 
SB Labs
AA Solutions said:
You'll have a bit higher variation, but it's nothing major. And beats the alternative of nothing, here's the math curtesy of grok ai:

Testosterone Cypionate vs. Undecanoate: Blood Level Comparison​

AspectTestosterone Cypionate (250 mg/week)Testosterone Undecanoate (925 mg/26 days)
Half-Life~7–8 days~20–33 days (avg. 26 days)
Dosing Schedule250 mg every 7 days925 mg every 26 days (~250 mg/week)
Peak Level (nmol/L)~27 nmol/L (day 1–2)~24 nmol/L (day 7–10)
Trough Level (nmol/L)~15 nmol/L (day 7)~11 nmol/L (day 26)
Peak-Trough Swing~12 nmol/L (~44% variation)~13 nmol/L (~54% variation)
StabilityTighter control, higher troughsLarger relative swings, low-normal troughs
Use CaseTRT, bodybuilding (flexible)TRT (less frequent injections)
DrawbacksWeekly injectionsLow-normal troughs, slower adjustments
Conclusion: Testosterone cypionate (250 mg/week, every 7 days) is slightly more stable than testosterone undecanoate (925 mg every 26 days) due to smaller relative swings (44% vs. 54%) and higher troughs (15 vs. 11 nmol/L), staying comfortably within the physiological range (10–30 nmol/L).
Click to expand...
Test C once a week is terrible for blood concentration, so essentially 925mg of test U every 26 days is slightly worse? That’s not good when it’s comparable to something bad.
 
Astro95 said:
Test C once a week is terrible for blood concentration, so essentially 925mg of test U every 26 days is slightly worse? That’s not good when it’s comparable to something bad.
Click to expand...
OP stated that he takes test C weekly, so I compared it with what he's already used to. I'm a big fan of e3d with bot C and E, but to each his own.
 
What levels might be based on MCT based TU at 600mg every 4 weeks.
 

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I'll be honest, I started taking 250mg of test C weekly in 2022 on the advice of a coworker, I've stacked it with other stuff a few times, but haven't really tried any other testosterone variances, and I haven't really had any lab-work done ethier, which I know I definitely need to do, I've always felt good so I just went with it, now faced with not being able to take the Cypionate weekly because of work I'll need to take Undecanoate, this won't be a ongoing thing, probably about 3 months, after that I am going to get proper blood-work done, I appreciate all the information/advice you guys have given me, and once these three hitches are done I would like to find some good cycles/stacks I can stick to and best works for me, I'm willing to try different approaches and I'll be definitely coming back here to pick people's brains and ask for advice as it seems you guys have a wealth of knowledge, thanks again.
 
AA Solutions said:
You'll have a bit higher variation, but it's nothing major. And beats the alternative of nothing, here's the math curtesy of grok ai:

Testosterone Cypionate vs. Undecanoate: Blood Level Comparison​

AspectTestosterone Cypionate (250 mg/week)Testosterone Undecanoate (925 mg/26 days)
Half-Life~7–8 days~20–33 days (avg. 26 days)
Dosing Schedule250 mg every 7 days925 mg every 26 days (~250 mg/week)
Peak Level (nmol/L)~27 nmol/L (day 1–2)~24 nmol/L (day 7–10)
Trough Level (nmol/L)~15 nmol/L (day 7)~11 nmol/L (day 26)
Peak-Trough Swing~12 nmol/L (~44% variation)~13 nmol/L (~54% variation)
StabilityTighter control, higher troughsLarger relative swings, low-normal troughs
Use CaseTRT, bodybuilding (flexible)TRT (less frequent injections)
DrawbacksWeekly injectionsLow-normal troughs, slower adjustments
Conclusion: Testosterone cypionate (250 mg/week, every 7 days) is slightly more stable than testosterone undecanoate (925 mg every 26 days) due to smaller relative swings (44% vs. 54%) and higher troughs (15 vs. 11 nmol/L), staying comfortably within the physiological range (10–30 nmol/L).
Click to expand...
It's very cool that it is able to do all that, thanks for taking the time.
 

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