Apologies if this is the incorrect place for this post. I figure it has to do with pens, so this may work?
I've recently made the switch to peptide pens and have become a huge fan of the convenience and consistency (thanks Randy!). Since I'm also on TRT, I started wondering whether testosterone could be used with pens as well.
After finding a forum thread where several people were doing exactly that, I decided to run some tests of my own.
Goal: Determine whether Testosterone Cypionate can be delivered accurately and consistently through a peptide pen.
Setup:
Pen: ConviPen (auto-injector)
Testosterone: Testosterone Cypionate 200 mg/mL in cottonseed oil
Needles: EasyTouch 29g 1/2" pen needles
I chose the ConviPen because it uses a metal drive rod and I suspected an auto-injector would have an easier time pushing a more viscous oil. I am still considering testing a manual pen (V4) for comparison.
Testing Performed:
Test #1: I loaded a cart into the pen and measured output directly into an insulin syringe. To do this, I inserted the syringe into the cart and dispensed a dose from the pen, allowing me to measure the volume.
Approximately 10 repetitions were performed.
Result:
Output was extremely consistent.
15 units delivered essentially what was expected each time.
Test #2: I then attached a 29g pen needle and repeated the testing by dispensing through the needle into the open end of a syringe. This method was less precise than Test #1, as some of the oil adhered to the sides of the syringe and could not be measured perfectly.
Approximately 30+ repetitions were performed.
Result:
Output remained consistent.
Measured delivery was roughly 1 unit lower than expected.
Because of this, I began testing a setting of 16 units to achieve an effective 15-unit delivery.
Test #3: I then did an actual subcu injection for my regular dose. When I pressed the trigger at 16 units, the dose indicator rapidly dropped to approximately 5 units remaining, then continued clicking all the way down to 0. I left the needle in place for approximately 10 seconds after the indicator reached 0.
This behavior was very different from my syringe testing and raises the question of whether tissue resistance affects delivery compared to bench testing.
Preliminary Conclusions:
• Testosterone Cypionate in cottonseed oil can be delivered through a peptide pen.
• A 29g pen needle appears to work (shout out to the forum users who stated this in another post!!)
• Pens are mechanically capable of pushing oil-based testosterone.
• I still need long-term validation through TRT labs to confirm that Total Testosterone and Free Testosterone remain consistent with pre-pen values.
• I am unsure whether an auto-injector or manual pen is ultimately the better platform for oil-based compounds.
Questions: For those who have experimented with TRT in peptide pens:
• Have you found auto-injectors or manual pens to be more reliable?
• Has anyone validated dose accuracy through bloodwork or measured output testing?
• What are some other factors I should be considering?
I'm still early in this experiment, but so far, things are looking promising!
P.S. For those wondering, I wasn't burning through my actual TRT supply for science. A friend had an old blended testosterone vial that was never going to be used, so it became the sacrificial test subject for this project.
Watch on RandyTube: DIY Topical Peptide Serum with GHK-Cu + Snap-8 | Base, Mixing & Clean Handling (Video Tutorial)
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