Welcome to the video everyone. Today as a guest we have Gil Tebak. Welcome Gil.
Thank you so much. Happy to be here as always. And we're going to talk about injecting testosterone for TRT of course.
What are the best injection sites, intramuscular versus subcutaneous, needle sizes and so on. So Gil, go ahead with the presentation. Okay, so first there's always this talk on all the groups about intramuscular versus subcutaneous.
So for starters I want to make something fairly clear. We're going to go over in fairly great detail the differences between the pluses and minuses of each injection site and I'll explain why some medications belong in one versus the other. But I also want to be clear about the real world effects of adherence and scar tissue.
So some guys inject on a daily basis and there's a lot of different reasons to do this. Personally, I don't find Most of the reasons that are often stated to have as much merit as people would like. I do see a benefit when someone is a hyper excreter or has low SHBG.
To say it's more stable, we're going to get into the pharmacodynamics over the slides. So I'll explain a little more on that. I don't think really that makes a big of a dent when you're looking at a longer ester.
So I think two to three times a week is more than sufficient for most guys with a Scipion type ester. But. when the guys go daily, that is the only time I would say a subcutaneous injection of oil-based medication would suffice only because the amount of holes you're going to be poking in that tissue over the course of your lifetime.
And for the sake of, you know, inhibiting scar tissue, if you will, over the course of long-term duration, I could see microdosing coming in a little handier in that regard from a purely scientific standpoint. you know, not talking about the social aspect of adherence and scar tissue from a purely scientific standpoint. I'm going to get into a couple of slides and explain why oil-based medications belong intramuscular. So I know this is your area of expertise being a dermatologist. Obviously, your layers of the skin are something that's going to be very familiar and I welcome your input on that.
So... I'm going to go ahead and start the slides here. So I'll do a quick screen share.
All right. And I'll bring that up here and you should be able to see it. Just let me know if you could see my screen.
Yes. Okay. So we've got subcutaneous versus intramuscular injections. Subcutaneous is somewhat of a social term that was accepted to define a layer of the skin called the hypodermis, which is an adipose tissue.
fatty layer that sits right below the actual dermis, also known as true skin. So I'll get into that right now and explain to you what's going on here. Got a little pointer there.
Okay, so here's the layers of the human skin. So this is not exactly drawn to scale. The epidermis, which is the top outer layer, consists of essentially five different layers.
The top layers are mostly dead skin and sebum, which is more of a protective layer. This is called squamous epithelial tissue. It's a flat layer of cells that's held together and it creates an elastic bond that allows you for a layer of protection.
If you go down a little bit into the lower layer, which over here they have a pretty broad, but in real life, this entire thing is about one tenth of one millimeter for all five layers combined. That's what's called a basal cell layer. of the epidermis and this is the only layer that actually contains cells that can multiply or go through the process of mitosis which eventually get pushed up to the top. If you go right under the epidermis we have a layer called the dermis which is generally split into two and the dermis is what's known as true skin. This is the area of your skin that is actually considered the only true skin layer which is consisting mainly of your hair follicles.
your exocrine glands, like your sebaceous glands, your sweat glands. It does contain blood vessels. Just to be clear, the epidermis, which is epithelial tissue, is avascular, which means it does not have any blood vessels whatsoever or nerves.
The dermis is actually not epithelial tissue. It is the first layer of connective tissue. and it does contain blood vessels and nerves.
So the nerve endings in your dermis are what give you the sensation of pain, pressure, temperature, et cetera, and that is transferred through the epidermis. And the blood vessels of the dermis also supply the epidermis with nutrients via a process called diffusion. So those are your first two major top layers, obviously split into five and two, which give you a total of seven.
And then you have your subcutaneous tissue, which I discussed earlier, also known as the hypodermis. Now, this layer here is essentially made up of fatty acids. This is an adipose tissue layer.
It does contain slightly bigger blood vessels than the dermis. It does contain nerves as well, but is primarily made up of adipose tissue or fat cells. And this is the thickest. This is why I said it's not drawn to scale.
This would be the thickest layer of the skin. Your dermis would be thicker than the epidermis. And then your subcutaneous generally would be the thicker layer. And this can range greatly from anywhere from, you know, a millimeter in the thinnest area, I think half a millimeter around your eyelids, for example, all the way to like the palms of your hands, where palms of your hands and soles of your feet are a little different. They're known as thick skin, whereas the rest of your body has thin skin and the thick skin doesn't have any hair follicles, but that doesn't really...
translate it into injections. The subcutaneous layer here is going to be the thickest area, and that can range up to about 14 to 15 millimeters. And then obviously, if your BMI is elevated or you're an overweight person, that's going to thicken up as well. So this would essentially be the thickest layer of the whole bunch.
And then underneath your subcutaneous layer, you're going to have muscle tissue. Okay. Your subcutaneous layer is primarily made up of fat cells.
that are stored energy. This is a majority of your body's fat. I think about 80 or 85% of your stored fat is in the subcutaneous layer as opposed to the visceral tissue layers. It's primarily a type of fat called triacylglycerol or TG, which is the fat stored for energy use that can be used and mobilized to other tissues later. If you go into the next slide here, you're going to see a typical subcutaneous injection.
We can tell by the color that this is a water-based injection. It could be insulin, for example, which is commonly injected in subcutaneous tissue and any other water-based peptide, if you will. So if you'll notice, they're using a longer needle here, but they're going on a 45-degree angle to avoid hitting muscle because they want to deposit this in the sub-Q. And if they went on a straight 90, they would probably pierce the muscle tissue.
So this is just for demonstration purposes. And just so you understand, this hair follicle would essentially... dip in to the dermis layer. All right. If you go into the next one, this is muscle tissue.
The muscle tissue is wrapped in a thick connective tissue layer called the epimysium. And this layer is elastic and it helps with contractions. However, once you pierce that layer, you're inside what's known as the muscle belly.
And the muscle belly has these little bundles of muscle fibers, which you could see here. These muscle fibers are covered in something called the endomycium. And then the bundles are covered in something called the perimycium.
And then the entire muscle belly is covered in the epimycium. So when you give yourself an intramuscular injection, you're piercing the epimycium and you're entering the perimycium into the muscle fibers within the belly. If you look at these little red and blue dots, these are blood vessels that flow throughout the muscle belly.
And then you'll notice inside of the perimyceum bundle here, you have additional blood vessels. And then you'll notice them around here, around the endomyceum. And then you'll even notice some blood vessels inside of the fibers.
So there's a lot of blood flow in the muscle. Okay, there's no fat layers here. It is essentially made up of proteins and amino acid chains. If you go into the next one here, this is different types of injections.
This is something that obviously I would assume Stephen does a lot in his practice. It's an intradermal injection. If you've ever had anything removed for biopsy, you would have lidocaine placed on a large angle like this right underneath the skin. And this is, again, the top layer of where your nerve endings are in the dermis. And this would serve to numb the area so that you can remove things either from the epidermis or things that...
root down into the dermis without any pain. So intradermal injections are usually numbing agents for the most part. If you go intravenous, That would be in the dermis. That is the first vascular part of your skin.
And intravenous is going to be the fastest absorption of medication. We'll get into that in pharmacokinetics on the next slide. And then subcutaneous, as we saw on the first slide, is going to be in the adipose tissue or the hypodermis.
And then you'll notice the same needle. Essentially, they're using on here the same needle. You'll notice the only thing that's changing is the angle. Intramuscular, it's going straight in through the...
epimyosin of the muscle into the fiber. So we're going to compare blood flow because blood flow is going to be the first step in absorbing into your plasma so that the medication can begin this distribution process. So comparing blood flow between adipose tissue, right? So it's also known as ATBF, which is adipose tissue blood flow. Comparing that to intramuscular blood flow is important to understand how the medication actually enters.
systemic distribution so that we know which one we should be using for which type of medication. So if you'll notice adipose tissue blood flow is variable and it's determined by metabolic factors. So what does this mean? Remember, it is stored energy in fat cells underneath your dermis.
Therefore, when you eat a meal, okay, fatty acids will be mobilized. They will be generally mobilized for storage into the hypodermis or subcutaneous layer through your blood vessels because of the nutrients you just consumed. This is called lipogenesis. When you are fasted and you are dipping into your fat stores, this is called lipolysis or the breakdown effect.
So that's when fatty acids would be transferred back into the bloodstream. So your blood flow or blood absorption from your adipose tissue or subcutaneous layer is variable and it's determined by metabolic factors. Okay, your intramuscular blood flow is variable, and it is determined by muscular contraction. The more your muscles contract, the more energy and oxygen they need, the more glucose they need, and the more blood flow they receive.
This is why when we train resistance, we get what's known as a pump or a muscle pump. This is nothing more than a rush of blood into the muscle tissue. And if you stop and think for a moment, what do you think happens more consistently throughout the day?
movement of muscles and don't just think working out think every single movement is a muscular contraction because muscle contractions are simply ways for your body to move your bone structure so every time you're moving your mouth or your hands or your legs or your feet or your neck or anything you're a contracting muscle so this happens far greater in frequency than metabolic factors of nutrition right so this is a more consistent blood flow you stream, if you will. Okay. Your adipose tissue contains sensory nerves and blood vessels.
That's what I discussed earlier. These are nerves that are responsible for sensation. They give you a sense of pain, of pressure, of temperature changes, et cetera.
And then your muscle tissue contains mostly somatic motor neurons. These are responsible for electrical pulses to cause muscle contraction. Now, I did look up a couple of studies. where they have found that there are certain pain sensors or receptors in the muscle.
However, they're nowhere near as delicate or sensitive as the sensory nerves in your adipose subcutaneous layer. Remember, everything you touch and feel with your hands and feet requires, and temperature, all this stuff for the sake of protecting you and allowing you to function, requires a hypersensitive nerve ending. Whereas the somatic...
motor neuron is essentially just a voluntary action of your brain firing a signal to tell your muscles to contract. The amount of pain receptors in muscle tissue is far less than that in the hypodermis. Okay. And then adipose tissue is hydrophobic.
What does this mean? It means it repels water. It does not like water.
Why? Because it is a lipid. And if you've ever put oil and water together, you'll notice they do not mix.
They repel each other. If you look at muscle tissue, it is hydrophilic. This means it loves water.
In fact, 70% of your muscle tissue is made of water. So if you were to inject a water-based substance into your subcutaneous, it would repel it, which means it would have a much easier time absorbing into the blood as opposed to intracellular. Whereas if you were to inject an oil-based, your subcutaneous layer would actually like it.
Okay, and it would want to hold on to that and it would have a harder time if you will to kind of Allow your blood to take that away. If you injected water into your muscle the opposite would happen you would actually hydrate the muscle tissue. Whereas if you injected oil into a hydrophilic substance, it would be repelled and it would be absorbed easier into the bloodstream.
So this is some contrasting views. It's not that one is better than the other. Again, it comes down to the type of carrier that we're using in our medication.
If we were using oil, your intramuscular is going to have these benefits. If you were using water, your subcutaneous would have these benefits. So now you got to understand pharmacokinetics and pharmacodynamics.
Pharmacokinetics refers strictly to the movement of drugs through the body. And I'll explain the four areas where this happens. And then pharmacodynamics is simply the body's biological response to the drug.
How does it affect us? So pharmacokinetics is four different things. It is absorption, distribution, metabolism, and elimination or excretion. Okay, and here's a little acronym to help you remember, ADME.
Okay, absorption, distribution, metabolism, and excretion. Absorption, we inject or ingest any sort of medication. Our body needs to absorb this medication in the form of getting it into the bloodstream. The bloodstream is then responsible for distributing the medication into the target tissues.
The liver primarily, and this will vary by medication, but primarily the liver. will metabolize or break down the compound into either its effective state or inactive state, depending on the drug. You have drugs that are called pro-drugs, and I'm sure some of you have heard of pro-hormones.
They're not effective until they're metabolized, and then they become effective. And then when you use an effective drug or an effective hormone, it is effective until it is further metabolized, and then it becomes ineffective in the form of the protein. testosterone, we all know it is metabolized in various ways. The liver will inactivate testosterone and make it ready for elimination through the kidneys. Aromatase will metabolize testosterone into estradiol or 17-beta-estradiol, which then has two sub-substrates.
And then your 5-alpha reductase will reduce testosterone into DHT. So these are all forms of metabolizing the hormone further. and then excretion. Okay, so these are your four pharmacokinetics.
Your pharmacodynamics, regarding testosterone, the biggest focus we always look at is the half-life. The half-life is very simple. For simplicity, I'll use 100. I'll give you 100 milligrams of the medication.
How long? Until 50 milligrams remains in plasma. And for cipionate, this happens to be seven to eight days with most people. With an anthate, it happens to be four to five days with most people.
The reason we always suggest cipionate at a minimum of twice per week is because we cut the half-life in half yet again, allowing us to go from 100 to 75 before we top it back off. We never drop to a half of a gas tank. So it avoids a rollercoaster effect.
Now, injectable testosterone esters follow a linear elimination half-life. This means that they are not dose-dependent. Okay, and follow me here.
It doesn't mean that dose dependency does not affect. how your body responds, it simply means the half-life or the excretion or elimination time is not dependent on dose. If you inject a thousand milligrams, your half-life would leave you with 500. If you injected a hundred milligrams, your half-life would leave you with 50. So this is an independent variable because regardless of the dose, it's a sliding scale. Okay.
Next thing we got here, what do we got? I believe that was the last slide. So the Yeah, this is essentially the gist of it. What I wanted to kind of touch on a little bit more was the first slide, which explains to you the different layers. You have to understand that when you're putting oil into this layer here, the blood flow is not going to be as efficient as it is in a muscle layer.
And you're dealing with a hydrophobic layer, which means that it loves... lipids or oil-based stuff and it dislikes water-based stuff. We don't want the tissues locally to absorb what we're giving them.
We want it to enter the bloodstream. The biggest problem is that when you do this, you are now taking the pharmacokinetics and you're changing them. So we know how medications work based on the half-life that they're designed for, because oil says for intramuscular use or injection. And they are then tested in all these studies you're looking at.
Up until recently when they started kind of manipulating based on popular demand for sub-Q, all of these previous studies that we had on the efficacy of the use of the medication is based on the intramuscular dosing. So when you start changing the pharmacokinetics of the medication, the rate of absorption, the effect of life and the excretion, now you're changing so many other variables, which is going to make the whole dialing in and that steady state we constantly talk about a lot more difficult. So what's your take on all of this, Stephen? Yeah, I completely agree because, for example, here in Belgium, we can only get sustenum.
And on the label, it also says for intramuscular injection only. And I knew a lot of guys that tried to inject it sub-Q, but they all get these kind of lumps and subcutaneous nodules, etc. I have seen them in my practice.
Yeah, and they happen again because now what's happening is your adipose tissue is absorbing. All of these, it's essentially expanding your tissue because it is absorbing, it's not releasing the carrier oil. Another thing, people always confuse esters with carrier oils.
There are two completely independent things. And ester is nothing more than molecular structures that are chemically attached to the molecule of the hormone in order for your body to require it to be cleaved off for usage. This extends the life of the medication.
The carrier oil... or the carrier bacteriostatic water, whatever it is mixed or constituted in, is really what we're talking about here. So whether it's cipionate, ananthate, sustenone, propionate, none of that matters because it is still an oil-based medication. The ester will determine the pharmacodynamics.
The carrier oil will determine where you should put this injection. Something that the bodybuilders often use called TNE, or test no ester, is a water-based suspension. of testosterone with a half-life of about 90 minutes.
And that is a water-based, and that is something that could be utilized subcutaneously. But this is not something we ever use in medicine. It's not TRT. It's not. So anyone on TRT that is presumably using an oil-based injection, I urge you, if it's not for the purpose of, you know, daily injections or preventing scar tissue in the long term, just use a shallow intramuscular approach.
It doesn't need to be deep. It doesn't need to be painful. In fact, I find intramuscular injections less painful than subcutaneous. Subcutaneous tend to irritate and kind of linger for a while, you know, when you're dealing with oil-based.
And remember, there's solvents too. You've got benzyl alcohol, benzyl benzoate that they use to compound these medications, and those kind of irritate the subcutaneous. So I'm not a fan of sub-Q unless it is absolutely needed when it comes to oil-based medication. Okay, Gil. Let's talk about needle sizes for both techniques, maybe.
Okay. What we teach patients often is two specific areas for injection. The first one that I like is the lateral belt, which is right in the side of the shoulder. It tends to be a fairly lean area in most people.
And again, we'll kind of touch separately on the more obese or heavier guys, but it tends to be a leaner area. Okay. So generally it's hard to...
hit a shallow part of the muscle with only a half inch needle in that area. Obviously, if you were to go in the belly and you have a little bit, you know, if you're in the double digits of body fat, even in the low teens, your belly's probably not going to hit, nor do I want to inject my abdominal wall, but you're going to find muscles that are not as vascular, a little bit tougher, and a little bit more resilient. I don't like the quads, and this question comes up a lot. We have a lot of nerves and a lot of blood vessels in the quads.
They're also very important muscle groups, not to sound a little silly here, but if I said, you know, I'm going to dramatically impact your ability to move a muscle in your body, I don't think you would choose your leg as one to inhibit. So injecting legs for an extended period of time over the course of years will develop scar tissue. And I don't think that limping around eventually is going to be pleasant.
So I avoid quads. I just, I don't see them as a necessity. especially for such low volumes. I mean, quads are big, glutes are big. These are areas that can handle, you know, three to five cc's of medication.
And I don't think that we need that with TRT, especially when you're splitting your dose two or three times a week. You're looking at a quarter, you know, to 0.3, 5.4, even half a cc in an injection. These are not areas that really require that type of injection.
So I like the delts. For guys that have a hard time reaching their delts, we teach them the ventral glute, which is a little area on the side of your hip. and even though it feels kind of bony, I mean, I've gone as far as an inch and a half in there, you're not going to hit your hip bone.
It tends to be, I think, close to about two inches on most guys. If you go with a half inch needle, you'll do just fine in that area. If you're a little heavier, half inch is not going to hit the muscle because you do accumulate fat in that area.
So you may need a little bit of a bigger sized needle, but most of the insulin syringes that come as a one piece connected are going to be half an inch. And if you're going to go between a 27 to a 29 gauge, 27, 28 to 29 is what I found to be the sweet spot. It alleviates pain. It minimizes risk for scar tissue. It is literally easy to do.
And the biggest complaint I hear from guys who have never tried or never been taught is that they have a hard time drawing medication, which is viscous, into an insulin syringe. So we teach patients in the office various techniques on how to do this the right way. So you draw with the insulin needle as well and you use it to inject intramuscularly? Yeah, so this is an insulin syringe.
This is a 1cc 29 gauge. This is a half inch syringe. You could see the needle, half inch needle.
Very small because my fingernail for perspective, very small and it is connected so you don't swap needles. You essentially draw into this syringe and then you inject with the syringe and then discard it in a sharps container. Very, very simple.
The one thing people have to remember, and I put some testosterone sipinate into a sterile generic vial here just to eliminate any pharmacy labels for the purpose of the video. We're not promoting any specific pharmacies or vendors, but essentially it's just testosterone sipinate in a sterile vial with a rubber stopper. People have to remember pressure. And this is where people kind of screw this up a little bit.
You have atmospheric pressure instead of the vial. So if you've ever worked with an air compressor and you've compressed the air and then as soon as you open that valve all the air pops out really quickly and the reason for that is we know that common sense tells us in physics that items are always going to move from high pressure to low pressure. It's called moving down a concentration gradient.
Okay we find this in osmosis we found find it with a you know a hydro pressure you know from water weight. And we find it in barometric or atmospheric pressure. So we have atmospheric pressure inside the vial, and we have atmospheric pressure outside around the vial.
And if they do not equal, then what's going to happen is air from here is either pressing out if the pressure is higher in the vial, or if the pressure is lower, like with a vacuum, air from the outside is going to push in. Oftentimes, we find that the air pressure in the vials is a negative pressure. And guys are just drawing and drawing and drawing and they're removing mass or material from the vial, but it is airtight pressure into a high pressure environment.
So the biggest thing they have to remember is to pressurize their vial before every injection. This essentially helps to push the oil out faster, okay, instead of fighting against the vacuum. So I'll show you real quick how to do it. It's super easy. As with any injection, we always want to take an alcohol pad and wipe the type of the vial for sterility.
And then you want to let it air dry for about five seconds. Don't blow on it, obviously. I say obviously, but I've seen people do it.
You want to draw air into your syringe. And I, regardless of how much I inject, I always like to have more pressure in my vial than I do out because it just helps to push the medication faster. So I'm going to use a full ml of air.
I'm going to go all the way to the back of the syringe. You introduce your needle on a 90 degree angle right into the vial, push the air in, and now when I pull back on the plunger, I'm creating a vacuum in the syringe. And I don't know if you could see how fast this is flowing with an oil-based medication, even though this is only a 29 gauge tiny little needle and everyone says well you can't draw with an insulin syringe it doesn't work well here we are coming up on about 10 seconds or so all right and i'm already at 0.3 of an ml so i'm gonna just knock those air bubbles put them back in and i got 0.3 I don't know if you could see. 0.3 of an ml.
Okay, so just to show you how easy this is. Done. That's it. Easiest thing in the world.
Can't feel a thing. There's no bleeding and done. Shallow intramuscular injection of, you know, one third of a cc.
And it's literally two, three times a week of doing that. And it is, I mean, it just can't get any simpler. So why do you want to mess with, you know, pinching your belly and having lumps and having these nodules and having all the, you know, the burning sensation and worrying about absorption and excretion?
I mean, it's just, it's intramuscular medication and it's administered with the tiniest little needle ever. I mean, I've seen guys do subcutaneous injections with bigger needles than that. And I just don't get it. I mean, we, when we do water-based peptides or HCG or ipamoralin or any of those, we're using a 31 gauge.
subcutaneous you can't even feel it in fact if you if you if you if you're not careful you'll bend the needle that's how much of a hairline it is so i believe i mean when you're when you're going um uh intradermal were you probably using a 28 29 yeah yeah 29 yeah and that was a 29 i just used i even use uh smaller than that it's uh 40 of an insulin syringe it says especially designed to inject botulinum toxin yeah So, I mean, I just used a similar syringe that they use for Botox for an intramuscular injection. I don't see the big deal, guys. I really don't.
Okay. I think you've covered it all, Gil. I mean, it's simple, isn't it?
Well, in Belgium, and I've heard in a lot of surrounding European countries, we only get these glass vials of one milliliter, 250 milligrams testosterone. Yeah. A lot of guys are always asking me and PMs, how do I have to do that?
I've seen those. I've seen that they're called ampules. And I don't like them because when you break the top, sometimes you get glass shards. I dislike ampules.
However, if you get the ampules, that's okay. What you can do is you can simply draw up, they're usually 1 ml, right? Exactly. You could draw them, depending on your dose, into two or three of these. little syringes right from the ampule and just store them for a week.
I'm not a big fan of having an oil-based medication like Cipionate, testosterone Cipionate, sitting in a pre-filled syringe too long because the solvents may eventually start to act on the rubber stopper. But again, if it's a matter of a couple of days, three and a half days apart, it's not a big deal. You know, you can always put them into a larger syringe, give it a little bit of an air gap. and leave them in a little shot glass standing up so it doesn't seep, leave an air gap so it doesn't touch the rubber stopper, and then just backfill your syringes when you need to. Or you could just literally just refill your syringes for, you know, a few days out at a time, and you're good.
So you don't have to inject the whole thing at once. It's not that big a deal. You could also buy sterile vials, right? A 10-ml vial, open up 10 ampules, use a mixing syringe, which is sterile.
and then transfer all of your ampules into this one vial. And now you've got like a four-month supply of your medication in a sterile vial as opposed to breaking ampules every couple of days. Okay, great tips. If people would want to reach you, Gil, how can they do that?
As always, my website is www.nextlevel.com. dietetics.com coaching and consultations are available worldwide for all things hormones nutrition and training so any questions i'm happy to look over labs answer questions do 30 to 60 minute consultations or eight week programs as needed okay and gil is very active in our facebook group with the same name as the channel trt and hormone optimization So thank you Gil for all you do for clarifying this for us. Thanks so much. My pleasure. Stay safe.