T Nation

Are We Losing Libido and Arousal Due to SHBG?

This was also my experience, 3 days after my injection I felt blue mood and avoided social interaction. I could feel the minor swings, this doesn’t happen on EOD. Working hard on losing weight so I don’t need to rely on the AI because keeping E2 in range is proving challenging.

I look forward to your report in 5-6weeks when the new protocol is stable. Right now I am trying M/T Just because I was sick of M/W/F it’s been 6 weeks and I feel fine actually no different. I was dialed in about 11 months ago. My current SHGB in July was 29. I did not change my HCG dose or frequency of 400iu Monday 400iu Thurs. I just added the T cyp to the HCG syringe. Now I only stick myself twice a week instead of 5 times a week.

Are you talking about androgen receptors?

Sounds very brosciency, any evidence to back up this claim. Lower SHBG simply means less testosterone will be bound to sex hormone binding globulin therefore more free T and less total T, SHBG can fluctuate quite a bit day to day, it’s not a “be all end all” hormone for diagnosis, sure, it can be important to diagnose hypogonadism if an individual has high TT but ridiculously high SHBG, however I don’t buy into the whole "guys with low SHBG NEED to inject ed/EOD, or the even more ludicrous claim that men with low SHBG piss out their testosterone at a very fast rate, also just because someone has low SHBG doesn’t nessecary mean they must have low E, if you’re having issues with libido there are a few variables that may be going on. You may need to

  • increase (or in some cases decrease) your test dose
  • other hormonal issues could be playing into libido (adrenals, thyroid etc)
  • neurotransmitters could be off, esp if clinically depressed
  • check what prescription meds you’re taking

People need to remember estrogen plays an important role with regards to wellbeing and libido

People seem to make their TRT protocals super complicated… Why? I also see a lot of people getting anxious about potential adverse health affects stemming from TRT protocals! I get anxious because I use doses higher than what most doctors would prescribe, therefore I’m anxious because there’s a legitimate chance of me running into issues later on in life. People getting anxious over replacing what they don’t have… Even by my standards (and I have serious anxiety at times) that seems silly


Blockquote I would kill for these numbers haha

I’m going to go 30mg eod and 1000iu hcg/week.

I’d like to injections the hcg at the same time as my 30mg test, but how much? 285iu eod? Is that calculation correct?

Yep. Same experience.

So your libido/arousal picked up after awhile on eod?

@unreal24278 this is a golden post. Truly. I have exactly zero patients on ED or EOD protocols. SHBG is a transport protein. It isn’t a hormone that gobbles up your test and gets rid of it. I have no idea where this shit myth came from. Plus we are talking about unesterfied testosterone. When you inject a depot of testosterone - unless it’s test suspension - it’s release time is dictated by the ester. I have no idea why people think if they have high shbg and they inject 200 mg of test it automatically all immediately becomes bound and not usable. The drug is released slowly over time. Some gets bound and some gets used etc etc. I feel like people forget or simply don’t know the way the drug is released into the body. It’s esswntially a time release formula. So to think you need to inject a time released formula every day which it is intentionally designed to release over a long period of time is silly and not useful. Shbg levels rise and fall throughout the day with thyroid fluctuations among many other things. Basing injection protocols off of a protein that moves around constantly makes no sense.


Why do some report feeling better with an eod protocol then?

I certainly did.

My honest opinion is that it’s mental. You think you’ll feel better so you do.

No. I did feel better. It could have been a lower e2 level

I’m a lawyer as my profession. I hate talking in a courtroom. It’s hard to concentrate and think.

On eod it was much more fluid. My thoughts came out better and were articulated more succinctly. There was a difference and it wasn’t placebo.

That’s awesome. I would never attempt to tell anyone how they feel. Another important Thing. How you feel in relation to neurology - your current feelings are typically a result of what you did 8 weeks previously. It takes that long for your neurotransmitters to alter enough to make changes. Keep that in mind guys.

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I’m going to try the eod protocol again but for
Longer, taking your advice.

My issue is that anytime I try higher doses, I feel anxiety and can’t sleep. I don’t know how you guys do supraphysio levels. Anything over 120mg a week makes me feel wacky. Maybe it’s just that I don’t let my body adjust to the higher levels. Idk.

Never used test suspension (water based) but TNE is awesome for a very quick jump in libido

The only reasoning I can see to justify doing this is the fact that one would have suuuuppppper stable T levels after peak concentrations have been achieved. Think if one was to inject say 20mg ( any dose ) of test C/day, levels would be very stable, however if the objective is to mimick natural T nadirs and peaks throughout the day TNE or test prop would probs be best however many can’t handle the PIP, and ED injections are annoying, also the idea of keeping test levels stable, meh, who cares, there’s another myth that the fluctuations in T levels from e7d protocals create issues with sides regarding Estrogen, however estrogen production/conversion should be correlated with the amount of testosterone in the body, therefore estrogen will decrease as testosterone levels decrease and since the ratio of testosterone to estrogen is more important than overall concentrations that myth is also likely bullshit. There’s a ton of other strange myths in the TRT/ bodybuilding world but I’m sure you probably know them better than I do!

I’m a transport protein, I think I’ve said this once before as a random joke and I’m saying it again

Now I’m a neurotransmitter, this is a picture of me #nonsensicalwackystrangesenseofhumour #nonbinary #fluid


I feel anxiety all the time! Pharmacologic, as in higher than replacement doses actually calm me down as they make me slightly more impulsive therefore I worry less, however I worry more about cardiac remodelling so it’s a catch 22, and being more impulsive isn’t particularly great either.

@unreal24278 at your dosages you don’t need to worry about that :slight_smile: stay away from deca and it’ll never be an issue for you.

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I appreciate the comforting words however I am positive there will be some form of cardiac remodelling from my bodybuilding, it’s tough to lift frequently with high intensity (natural or not) and not end up with LVH, I doubt this in itself has a serious detrimental effect on cardiac function, however the use of anabolic steroids (say 200-250mg/wk of test), over time will probably have a subclinical detrimental effect on my cardiac function. To add to that if I ever decide to compete I’ll drop my test down to 125mg and add 125mg of mast/wk, while this is a low dose, I seem to do fine on low doses, and then drop the test a week out and add more mast (say 200mg/wk), just stating what I intend to do, mast is def harsher on the cardiovascular system than test, not sure about cardiac remodelling but with regards to it’s effect on cholesterol, over time this could probably do some damage, to add to that I’ve used nandrolone in the past, never over 120mg/wk however I have used it, nor do I intend to use it again, actually thinking of throwing the remaining amount I have away but damage may have already occured on a cellular level, probably, not significant enough to make much of a difference though, DNA damage happens like 10,000 times every day in humans. Also tried anavar before, probably took a big ol shit on my lipid profile while I was taking it, although I love the way it makes me look and the pumps it gives me it fucks with my BP and the lipid issues aren’t worth it either, hepatotoxicity I’m not too concerned about, esp since a large portion of var appears to be metabolised by the kidneys. buuuuuuut BP issues and obvious cholesterol strain make it a no, I’d use a very low dose (say 100mg) of EQ as an experiment but the dramatic effect on RBC/HCT puts me off, will probably try it in a year or two.


I somewhat disagree with your thoughts on test cyp and that it’s designed to release slowly over time (that part I agree with) and that infrequent injections won’t help anything because of the same (that part I disagree with).

Remember, smaller, more frequent injections will lead towards lower estrogen conversion in theory, regardless of whether the test is in suspension or not. THAT, right there, is the goal of infrequent injections… lower e2, which some may feel better with.

A large test injections in a suspension will create more estrogen than a smaller injection in the same suspension. (don’t want to debate benefits of high e2 or low e2 here either)

Really, the body was designed for smaller bursts of test. In a TRT world, gels would be the most ideal transport medium and it’s an everyday application… Some just can’t obtain good numbers this way. Even most of the notable TRT experts, like Crisler and Saya tout the advantages of EOD or even daily injections.

Sometimes I think you intermingle and mix TRT with bodybuilder designed protocols. Of course I say all this with much respect to your profession.

Quoting stuff from Dr. TheoriesUnreal24278has @roscoe88

Yes, our bodies natural testosterone production fluctuates about 30 percent in any given day with peaks during the morning and nadirs before we go to sleep, during sleep the pituitary gets to work yeeeeeeeeeeeeeeeeeeeeeeeeet. ED or EOD injections of test CYP will produce minimal daily fluctuations in testosterone levels, therefore it isn’t really mimicking natural physiology. If you’re that hellbent on mimicking natural function, then test prop or test suspension is the way to go (or gels if they work for you)

When bodybuilders take test prop, tren ace, test suspension, mast prop (anything short ester) they inject ED or EOD to keep levels relatively stable, however taking test prop ED in the morning will mimick the natural peak and nadir system the body has, even if the doses are supraphysiologic, by your arguement it’s still mimicking natural physiology (with regards to daily peaks and nadirs) than the average TRT protocal. Injecting every day is just a pain in the ass (literally), applying gels every day and not being able to shower or exercise for many hours is highly irritating, and in my opinion isn’t ED shots to mimick natural physiology isn’t nesseccary for a good TRT protocal, who gives a fuck if mother nature designed us to be that way, SCIENCE has a leg up on mother nature (this is a joke… kind of)

now were gonna debate this (just kidding)

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An interesting read @roscoe88

Role of estradiol in the brain

The effect of estradiol on libido is seen at various levels of regulation, starting with direct effects in the brain (Figure 1). Areas of the brain that control sexual behavior in mammals are thought to do so via pheromones that induce specific sexual effects on the autonomic nervous system, including changes in mood and sexual arousal. Pheromones produce increased activity in the medial preoptic area/anterior hypothalamus.1 Neurons, the most basic electrical information-transmitting cells in the central nervous system and peripheral nervous system, as well as astrocytes, star-shaped glial cells which fulfill a number of functions in the central nervous system, both convert testosterone to estrogen with aromatase. The preoptic area and anterior hypothalamus contain the highest levels of aromatase and estrogen receptors (ERs) in male rodents.2,3 Similarly, it is well known that selective serotonin reuptake inhibitors diminish libido. Serotonin receptors follow a pattern of distribution similar to that of ERs in the brain.4 However, the interaction of estradiol and serotonin is complex and will subsequently be addressed. Finally, aromatase activity is highest in the brain during development. Thus, not only does estradiol modulate sexual behavior in the adult male, it also appears to organize the early brain to program sexual behavior.3
Estradiol effect at low testosterone levels

To discern the effect of estradiol, it is important to evaluate its effect on libido at both low and normal levels of circulating testosterone. Decreased testosterone is clearly associated with low libido in males.5 In men with diminished testosterone, the administration of exogenous estradiol has been shown to increase libido.6 This finding is supported by rodent studies demonstrating that castrated animals given exogenous estrogen show an increase in sexual activity in a dose- and temporal-dependent manner. 7 In addition, in a unique case report of a male patient with aromatase deficiency and hypogonadism, both estrogen and testosterone were required to increase libido, whereas neither hormone could achieve the effect alone suggesting that estrogen plays a necessary role in sexual desire in the setting of low testosterone.8
Similarly, patients with prostate cancer treated with androgen deprivation therapy (ADT) serve as a good model for the influence of estrogen on libido. When castrate levels of androgens were reached (T <50 ng dl-1), uniform adverse effects of hot flashes, erectile dysfunction (ED), and decrease in libido were reported.9 When comparing androgen receptor (AR) blockers versus castration, the former had better outcomes in maintaining sexual activity, presumably by increased testosterone conversion to estrogen.10This evidence, though indirect, does perhaps suggest that elevated estrogen in men with low or absent testosterone can sustain libido. In addition, administering estradiol to men undergoing ADT for prostate cancer could possibly reduce damage to areas of the brain associated with sexual performance. Thus, an overall increase in sexual quality of life could be achieved.6

Role of estradiol in eugonadal men

While estradiol has been shown to have a positive effect on libido at low levels of testosterone, a limited number of studies have looked into the effect of estradiol supplementation in eugonadal men and reported conflicting results. One study with continuous estradiol administration in men who had normal testosterone levels showed decreases in sexual interest, fantasy, masturbation, and erections.11 In contrast, a randomized, double-blind study conducted on 50 men ages between 20 and 40 years demonstrated that sexual activity was unaffected.12
Uncontrolled case reports also have shown conflicting results. A man with aromatase deficiency was noted to have a relevant increase in sexual behavior with estrogen supplementation,13 while other aromatase-deficient men noted no change in their sexual function.14 These natural models, which have the potential to provide some clarity, along with results of the limited trials undertaken, have not provided definitive evidence one-way or the other regarding estradiol’s effects on libido in the eugonadal male.

Role of estradiol in hypogonadal men treated with testosterone supplementation therapy

Perhaps, most relevant to the discussion is the use of testosterone supplementation therapy (TST). The goal of TST, regardless of the method used, should be to maintain not only physiologic levels of testosterone, but also its metabolites, including estradiol which optimizes libido.15
In men with secondary hypogonadism (functioning testes and relatively low levels of luteinizing hormone [LH] and testosterone), clomiphene citrate was used to increase testosterone by acting centrally on the ER weakly. Clomiphene citrate administration raised endogenous testosterone while increasing the testosterone to estradiol (T/E) ratio.16 Also, in a later study, clomiphene citrate administered to hypogonadal men produced an increase in libido, energy, and sense of well-being.17
In 2013, Finkelstein et al . looked at the effects of testosterone and estrogen on male sexual function. They found that the administration of testosterone with and without aromatase inhibitors markedly impaired sexual function when aromatization was inhibited.18 In addition, a study by Ramasamy et al . in 2014 showed that libido was increased in men receiving TST when testosterone levels were >300 ng dl-1 and estradiol levels were >5 ng dl-1. Most compelling is the fact that in men with serum testosterone <300 ng dl-1, sexual drive was seen to be markedly higher when estradiol levels were >5 ng dl-1.19 In addition, when patients with low testosterone were treated with letrozole, a potent aromatase inhibitor, libido was decreased, suggesting that complete elimination of estradiol and decreasing the T/E ratio too severely, adversely affects sexual desire in men .20 These studies provide evidence that both estrogen and testosterone are necessary for normal libido in testosterone-deficient men. Clinically, the dependence of libido in hypogonadal men on both testosterone and estrogen indicates that a cautious approach to the use of aromatase inhibitors is warranted and that the T/E ratio has an impact. It might be reasonable that while prescribing TST one should monitor the levels of both testosterone and estrogen and their relationship to each other.
Clearly, the effect of estradiol on male sexual desire is linked to testosterone levels, as there are different outcomes when estrogen is administered at low and normal testosterone levels. Another example of this duality is seen in men with androgen resistance, where unfettered estrogen is able to stimulate subsequent breast development. However, in men with normal androgen receptor activity, estradiol is unable to stimulate breast development.(If you have gyno issues it’s not high e2 it’s androgen resistance!!) 21 This is thought to be due to an imbalance between the inhibitory and stimulatory effect of these hormones.22,23 Whatever the pathophysiology in breast development or libido, these hormones seem to be inextricably linked in the complicated physiology of male sexuality and development.
Finally, the effect of estradiol on mood must be considered. As mood can correlate with sexual interest, it is reasonable to consider these data when discussing the role of estradiol on libido. While cognition, well-being, and depressive symptoms improve in men whose low testosterone levels were corrected,24,25,26 higher levels of estrogen also have been associated with less depression in older patients of both sexes. 27In addition, estrogen supports serotonin levels and affects the amount of 5-HT receptors in the brain, and depending on receptor subtype, there is sexual inhibition or facilitation.28,29,30 A recent study showed a significant positive correlation between endogenous plasma estradiol levels and cortical 5-HT2A binding in men, with no independent effects on these receptors from testosterone.31 In addition, when serotonin binds to these 5-HT2A receptors in the cortex, limbic system, hypothalamus, and midbrain, sexual desire is inhibited with subsequent induction of refractoriness and sexual satiety.32 The interaction of estrogen with serotonin is complex, with overlapping influences that reaches beyond sexual desire including mood regulation and cognition.33 This fact makes its true impact on sexual desire and behavior difficult to fully elucidate.

Estradiol and erectile function and more - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4854098/

I think I’ve read that series of studies and it’s quite interesting. What it doesn’t seem to indicate is what levels of e2 are most optimal.

Im going to run the eod protocol for a couple
Months to see my reaction. If I can’t see any increase in arousal I will go back to e3d or even weekly shots, but at a higher level than normal. Maybe 125-150mg a week. I’ll push through that weird period at the start where I feel anxious, hopefully letting my body acclimate.

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