Effectiveness of subcutaneous injections

Genetic Freak

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So recently I decided to try subcutaneous injection protocol with disappointing results:

Previously 0.5ml (250mg/ml testosterone enanthate) 1 injection / week, at week 5, blood test on day 3 post injection, at 9 am.. = Testosterone 30 nmol/L, Oestradiol 244 pmol/L...


Subcutaneous injection 0.2ml X 2/week (250mg/ml testosterone enanthate, same batch as previous) at week 5, blood test day 3 post injection, at 9am = Testosterone 9.4 nmol/L, Oestradiol <200 pmol/L..


Having read several papers of the pharmacokinetics of subcutaneous testosterone injections, promoting slower release times, lower plasma peaks, and reduced aromatization, I thought I'd give it a go...

Disappointed with the end result of blood testosterone..
 
That's a bit disappointing mate. I didn't register much of a difference between IM and SubQ when I used to do it about 10 years ago. Trouble is I ended up with bee-sting like lumps wherever I injected SubQ so had to stop. Even now there are still some small nodule-type lumps under the skin.
 
That's a bit disappointing mate. I didn't register much of a difference between IM and SubQ when I used to do it about 10 years ago. Trouble is I ended up with bee-sting like lumps wherever I injected SubQ so had to stop. Even now there are still some small nodule-type lumps under the skin.

No wonder I've lost 5kgs since Christmas..
 
Is it just not releasing as fast, and has a lower peak... or a peak on a different day?

It's still 125mg of test, it has to be metabolized at some point right? It cant go to "waste" from being sub q, can it?
 
Is it just not releasing as fast, and has a lower peak... or a peak on a different day?

It's still 125mg of test, it has to be metabolized at some point right? It cant go to "waste" from being sub q, can it?

The dose was 0.2ml X 2/week test-e 250mg/ml, compounded over 5 weeks..

Each injection should equate to about 32mg X2/week after the ester weight has been removed.. (64mg).. = 9.4 nmol/L..

What we don't know is the bioavailability of subq tissue (we must assume from blood testing that it is significantly less than what Minto et al. showed for IM injections ie: 72% glutes, 56% quads, 52% delts, from memory)..

What we know about pharmacokinetics (what the body does to a drug) Once injected the hormone forms a bolus in the interstitial space (space between cells), its transport is slowed by the ester, once the hormone reaches the bloodstream it is exposed to hydrolase and esterase which breaks the ester bond at 17b-hydroxyl position..

Once cleaved of its ester the free hormone can be taken up by transport proteins such as SHBG, serum albumin, which protect it from hepatic metabolization..
Remember there will also be a free (unbound portion) of hormone still in blood, prior to and post uptake by transport proteins..

This free portion of hormone is exposed to various metabolic enzymes such as CYP3A4 etc, that break it down allowing it to be removed from the body.. I assume the lymphatic system might remove some portion of free hormone (I have no data on this, just surmising)..

Clearly from blood tests, testosterone was not converted via aromatase to estrogen, as blood oestradiol levels were significantly lower than previous...

I might assume from all this that a larger portion of hormone injected subq is exposed to greater metabolism, by whatever means..??

Which sucks..!!
 
I'd suggest it simply gets enzymatically broken down as you suspect (and/or disabled by immune cells) before coming into contact with androgen receptors, and is thus wasted. Maybe you have a high density of lymph vessels where you're injecting? SubQ above the glutes might work better, where there's usually less.
 
I recently read some blood work where a guy went from IM 3 times a week, to Sub Q every day. The results were a little odd in my opinion but he went from running 300mg/week on the IM injects to 140mg/week Sub Q. He was hoping he could achieve the same levels or at least close going sub q with a lower dosage but here are the results. I'll just quote his post.


"Decided to try the subQ trt but 10mg ED seemed too low so I went with 20mg ED for 3 weeks. Normally I stay on 100mg pharm cyp MWF and pharm adex .5mg Monday and Thursday. I get bloods done Monday morning. Last shot was Friday morning. I absorb test very fast. Here are my #'s that way.

Total test 1096 range 250-1100
Free test 395 range 35-155
Estro 26 range < 39

So I switched to 20 mg every day for three weeks and lowered my ADex to .25mg Mon and Thurs. bloods done 24hrs after last 20mg subQ shot. Results:

Total test 796. Range 250-1100
Free test 236. Range 35-155
Estro 52. Range < 39

I'm glad I didn't do 10 mg every day as that would've been entirely too low for me.I guess the above would be acceptable numbers but I don't know how some are claiming to get equal or higher numbers off a way less dose. Maybe that works for them but not me. I'm glad I did the experiment though because the every day shots were getting a little annoying."




I found it odd his e2 was elevated, but he did lower the AI dose, but his Testosterone dose was also significantly lowered. Weird
 
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Was this test e2 specific or did it test for e1/e3 too? Also testosterone converted to dht in the skin too?

Try something that can't aromatise and is already a dht analog? Or test of all of them?
 
Was this test e2 specific or did it test for e1/e3 too? Also testosterone converted to dht in the skin too?

Try something that can't aromatize and is already a dht analog? Or test of all of them?

The test was for oestradiol (E2).. I'm not concerned about non aromatizable compounds, as basic testosterone fulfills my needs for TRT..
 
Was this test e2 specific or did it test for e1/e3 too? Also testosterone converted to dht in the skin too?

Try something that can't aromatise and is already a dht analog? Or test of all of them?


That wasn't really my reasoning for posting that. I was pointing out that with sub q on 20mg/day totaling 140mg a week has his level at 796.

Where injecting IM 3 times a week totaling 300mg had his levels at 1096.



In comparison sub q is a much better number considering the dose, but it seemed to elevate his e2 a little more.
 
There's more aromatase activity in SubQ tissue/fat than muscle, it could account for some of the increased systemic E2.
 
There's more aromatase activity in SubQ tissue/fat than muscle, it could account for some of the increased systemic E2.


Makes logical sense being fatty tissue, not sure why I didn't put 2 and 2 together. Thanks
 
The test was for oestradiol (E2).. I'm not concerned about non aromatizable compounds, as basic testosterone fulfills my needs for TRT..
You missed the last part testosterone is converted to dht too, maybe that's where the extra is going?
 
You missed the last part testosterone is converted to dht too, maybe that's where the extra is going?

I realised something today.... After several weeks injecting IM gluteal, urination is no longer an effort as it was with subq..

It appears subq could have been responsible for greater DHT conversion, resulting in BPH..
 
Have you had a DHT test before mate? How about PSA?
 
Genetic Freak: thanks for posting your interesting results.

You could raise your dose to compensate for what appears to be a metabolic peculiarity in your case (perhaps a peculiarity shared by others, which is why I am glad you posted it). Though the possible undue DHT conversion is a bit concerning. Perhaps you could try concurrent 5ARIs, but that has its own drawbacks, I grant. Sub-q is a great option for men because of not having to undergo ritual minor self-torture. Your case suggests that we have to be cautious; there are men for whom sub-q may not work very well.

But generally, the clinical experience with sub-q testosterone has been good: (I'm posting this because it just came to hand; there is more):

http://www.healio.com/endocrinology...ective-in-female-to-male-transgender-patients

Subcutaneous testosterone therapy safe, effective in female-to-male transgender patients

April 12, 2017

In female-to-male transgender patients, subcutaneous testosterone therapy was safe and effective and was the preferred route of therapy in patients previously receiving intramuscular injections, according to findings published in The Journal of Clinical Endocrinology & Metabolism.

Daniel I. Spratt, MD, of the division of reproductive endocrinology and infertility at Maine Medical Center in Portland, and colleagues evaluated 63 female-to-male transgender adults electing to receive subcutaneous testosterone therapy (mean age at completion of dose titration, 27.6 years) for gender transition to determine whether subcutaneous administration is safe and effective.

Serum total testosterone levels within or above the normal male range were reached by all participants, and mean total serum testosterone was 702 ng/dL after participants were receiving the optimized testosterone dose for 0.5 to 42.7 months. The median testosterone dose was 75 mg to 80 mg per week; 31.7% of participants reached normal serum testosterone concentrations at 50 mg per week, 54% at 75 mg to 80 mg per week, 11.1% at 100 mg per week and 3.2% at 150 mg per week.

Among the 53 participants who were premenopausal, 96.2% experienced amenorrhea.

Normal serum total testosterone levels were achieved by all participants regardless of BMI category.

Twenty-two participants initially receiving intramuscular injections initiated subcutaneous therapy; two reported a mild preference for the subcutaneous injections, and the remaining 20 reported a marked preference.

"Data from our patients indicate that long-term subcutaneous administration of testosterone cypionate to female-to-male transgender patients is effective, safe and well-accepted," the researchers wrote. "Because our patients were genetically female with low endogenous testosterone secretion, the normal male levels of serum testosterone necessarily resulted from absorption of the testosterone that was administered subcutaneously. Sustained efficacy for more than 6 months of therapy was demonstrated. Our observations extend information reported in preliminary short-term studies in hypogonadal men and young female-to-male transgender patients as well as a pharmacokinetic study in hypogonadal men." - by Amber Cox
 
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better: 39 hypogonadal males:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4721027/
Sex Med. 2015 Dec; 3(4): 269–279.
Published online 2015 Sep 17. doi: 10.1002/sm2.80
PMCID: PMC4721027
Pharmacokinetic Profile of Subcutaneous Testosterone Enanthate Delivered via a Novel, Prefilled Single‐Use Autoinjector: A Phase II Study
snip
Results
Both doses of SC TE achieved normal average concentrations of serum T within a 168‐h dosing interval after injection. Concentration ranges were similar at all time points following 50‐mg SC TE injections and following the third injection in the 100‐mg arm. Mean steady‐state T concentration at week 6 was 422.4 and 895.5 ng/dL for the 50‐ and 100‐mg SC TE arms, respectively. SC TE demonstrated PK dose proportionality. SC TE restored normal serum T with low variation relative to 200‐mg IM without clinically significant adverse events.
 
I like the sound of a novel pre-filled autoinjector ;)
 
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