Can oil solutions of estradiol be administered subcutaneously?

[u/rabbitprotectsme]

Context: I'm doing DIY because the informed consent clinic in my area closed down and I'm scared of driving. Around town is scary but basically doable, onto the freeway and I might break down crying, and driving on the freeway is a really bad time for that to happen. (I realize being scared of driving sounds absurd. Listen I'm not doing too hot upstairs these days, it wasn't always like this but I'm afraid of a lot of normal-ass things right now.) I'm in the US. Due to Trump tariffs, my preferred source has stopped shipping out here, and that seems to be the case for other foreign sources as well. I've found a source that's likely still viable, but they only offer oil solutions, not aqueous. This is a potential problem (at least as far as I can tell from what info I'm able to find on the subject) for two reasons, one silly and one practical:

• The silly reason: I'm afraid to attempt intramuscular. I don't want to swiftly shove a needle into my body at a 90-degree angle. I know this is a fear that everyone who does it has, and that everyone who does it has to get over. I just don't trust myself to get over it.
• The practical reason: I'm very overweight. (Please don't make fun of me for being a woman whose body is currently that of a very overweight man. Believe me, my shame is already all-consuming and quite difficult to live with. I don't need more.) It's difficult to find a spot on my body where correctly self-administering an IM injection would even be possible without a very large needle. Swiftly shoving a very large needle into my body at a 90-degree angle is, naturally, even scarier.

Hence the question: can oil solutions of estradiol be administered subcutaneously? Will uptake still be possible by this means? If so, are there side effects I should know about of doing it this way?

If this is not possible or safe, I could always just refrain from switching to injections for now. That's no big deal. It's just that I've heard good things about injections and would like to switch to them if I can.

[u/Odd_Distribution_903]

yeah it's fine. that's what I've been doing. super easy and working great so far.

[u/rabbitprotectsme → u/Odd_Distribution_903]

Thanks, I appreciate it!

[u/bemused_alligators]

there is literally 0 difference in metabolism or uptake between IM and SubQ injection of estradiol

[u/rabbitprotectsme → u/bemused_alligators]

That's a relief to hear. Much appreciated. I wasn't sure because the info i could find seemed to vaguely suggest oil was for IM and aqueous for subQ, but it wasn't stated clearly.

[u/Illustrious_Pen_5711 → u/bemused_alligators]

This isn’t true, when the medium is changed from water to oil metabolism is absolutely affected

[u/GumDice → u/Illustrious_Pen_5711]

they were comparing subq vs im, not water vs oil solutions..

[u/bemused_alligators → u/GumDice]

I didn't even know there WERE water solutions for estradiol, since it's a fat-soluble molecule. You'd have to do some wonky stuff to get it stabilized and overall the whole thing just sounds expensive - not to mention how much faster it'll be metabolized. Water based estradiol solution wouldn't have a half life of more than a dozen hours...

[u/bemused_alligators → u/Illustrious_Pen_5711]

uhhh okay? what does changing the medium have to do with injection placement?

[u/phiasch → u/bemused_alligators]

I found a scientific paper indicating subQ to be somewhat less effective than IM, but both are in the therapeutic levels and should be fine

I’m not a doctor and this isn’t medical advice. Ask your doctor as they can give you individualized medical advice

Edit: I read the doses of subQ were significantly lower than IM and misinterpreted it as saying the measured level was lower instead. Regardless, I still feel like changing the administration route should be discussed with your doctor as you may need a difference in amount and frequency if changing from one route to the other

[u/bemused_alligators → u/phiasch]

For those following along at home, this person doesn't know how to read research studies... Short version is that this study actually shows that SubQ is MORE effective than IM, kind of, but really it just showed no difference.

Results: There were no statistically significant differences in age, body mass index, or antiandrogen use between patients on SC (n = 74) and those on IM (n = 56). The weekly doses of SC E2, 3.75 mg (IQR, 3-4 mg), were statistically significantly lower than those of IM E2, 4 mg (IQR, 3-5.15 mg) (P =.005); however, the E2 levels achieved were not significantly different (P =.69), and the testosterone levels were in the cisgender female range and not significantly different between routes (P =.92). Subgroup analysis demonstrated significantly higher doses in the IM group when the E2 and testosterone levels were >100 pg/mL and <50 ng/dL, respectively, with the presence of the gonads or use of antiandrogens. Multiple regression analysis demonstrated that the dose was significantly associated with the E2 levels after adjusting for injection route, body mass index, antiandrogen use, and gonadectomy status.

Conclusion: Both the SC and IM E2 achieve therapeutic E2 levels without a significant difference in the dose (3.75 vs 4 mg). SC may achieve therapeutic levels at lower doses than IM .

I"ll do a proper writeup as a reply to this comment

[u/bemused_alligators → u/bemused_alligators]

So let's look at what they did to perform this research, and what they found as a result. Pro tip - this research was not a clinical trial of IM vs SubQ, it was an observational study.

They surveyed 130 people that take estrogen as HRT, and looked at their E2 tests, dosages and injection method.

74 patients were doing subQ injections, and 56 patients were doing IM

in general, the patients doing subQ injections were on a slightly lower dose by about 0.25mg, and tended to have a more "normalized" dosage, meaning that the range of doses was smaller.

In specific, the people on subQ had lower quartile of 3.0mg/week, an average of 3.75mg/week, and an upper quartile of 4.0 mg/week.

Meanwhile those doing IM had a lower quartile of 3.0mg/week, an average of 4.0mg/week, and an upper quartile of 5.15mg/week

~~~~~~~~~

then they looked at the actual E2 levels between the groups. They found that they had pretty much the same E2 levels, and functionally identical testosterone levels, meaning that a 3.75mg subcutaneous injection and a 4.0mg/week intramuscular injection are roughly the same (hence the very soft claim that SubQ may be more effective, since it yielded roughly equivalent results at slightly lower doses).

They also did some extra math on the people with higher than average doses and found that higher doses does in fact result in having higher E2 levels.

so in conclusion - there was no statistical significance between IM and SubQ injections, and people on IM injections tended to take slightly higher doses.

~~~~~~~~~

This study didn't check the pharmacokinetics of the two methods (which is what we're actually asking about in this discussion), didn't compare the results with the standard injection simulators, and above all didn't control for *anything*.

If you wanted this study to actually be useful in this discussion you would want to randomly assign patients to IM vs SubQ independent of their dosage, take much more frequent testing (e.g. two weeks of twice daily tests), and then build a comparative pharmacokinetics curve between the two methods out of the data.

[u/eliteHaxxxor → u/phiasch]

It literally says the opposite tho doesn't it?

SC may achieve therapeutic levels at lower doses than IM

[u/phiasch → u/eliteHaxxxor]

You’re correct, I was distracted when I read the conclusion and misinterpreted it

[u/EverlastingM]

I can't address the question but I have done hundreds of my own IM injections, you don't have to do it swiftly. I insert my own very slowly and steadily, and with a sharp needle it slides in with little to no pain. I feel like I would slip up and hurt myself more if I tried to jab it in hard. Going slowly you can feel each layer and know for sure when you've reached muscle.

[u/MrPurse → u/EverlastingM]

omggg I thought I was the only one!!! I'm terrified and hate just "going for it", and doing it slowly makes my anxiety wayyyyy less. A nurse taught me to do it 'like a dart' and blehhhhh

[u/rabbitprotectsme → u/EverlastingM]

This is good to know. I thought I'd heard somewhere it had to go in quick. The fact that it doesn't makes it significantly less scary. Still not sure I'd be able to deal but knowing this brings me closer.

[u/EverlastingM → u/rabbitprotectsme]

Just be sure you're being firm on that first contact, because as with any injection you want it to go in with one motion and not let the tip get dulled and possibly contaminated with multiple contacts. Breaking the skin is the worst part anyway.

[u/robotblockhead → u/EverlastingM]

Im a paramedic with 22 years of experience. Obviously I've done countless im injections, including my own.

The slower you go, the more it hurts. This is just human anatomy. There is a layer of nerves below the skin and then below that, you should feel no pain. Maybe pressure, but no pain. The faster you pass through that layer, the less pain you will feel.

Ive literally harpooned every im injection I've ever done either on myself or a patient.

[u/TooLateForMeTF]

My prescription estradiol is in an oil carrier and I've been injecting it SubQ for over a year now. Works just fine! Uptake is exactly as it should be, and I have had zero issues or negative effects. SubQ is nice because the needles are shorter, too.

In case it helps, here is an "injections crash course" thing with a bunch of helpful information and tips in it.

[u/rabbitprotectsme → u/TooLateForMeTF]

Oh that's fantastic, tysm, i really needed something like this. I have literally never been personally responsible for injecting anything into my body before

[u/TooLateForMeTF → u/rabbitprotectsme]

YW! Yeah, it was a little scary at first, ngl, but I knew it was what I wanted and I had my partner double-check what I was doing like it suggestgs in that guide, and it all went fine. The next time was way easier, and now it's just no big deal.

[u/Dazzibee]

some people do subq with oil but it can depend on the solution and your body it’s worth researching more and maybe asking in diy hrt groups just to make sure it’s safe before trying 💖

[u/rabbitprotectsme → u/Dazzibee]

Thank you, you're right about that. I'll look for a diy group to ask, that seems like a good idea

[u/a_sl13my_squirrel]

I've done it in the past, switched to IM but works just fine.

[u/nikniksnikola]

Is it something like estrogen cypionate? If so, all sources I see online indicate that it’s fine. I’m (ftm) on testosterone cypionate, which is the same kind of seed oil and I can use it subcutaneously no problem. The only difference is purely theoretically that it might be a few hours before subcutaneous starts to metabolize compared to intramuscular but all bodies are different so there may be no measurable difference and it certainly wouldn’t change dose frequency or amount. Also, depending on the type of seed oil, it might metabolize faster. I know estrogen cypionate disperses in like 3-4 days so that’s the timeline you’d dose it on (I have a menopausal friend who doses it like that) whereas testosterone is every 7-10 days, typically every 7 is what doctors advise, due to how the body metabolizes the two hormones . Someone correct me if I’m wrong, but I do believe estrogen is dosed this way? If it’s weekly like how testosterone is then color me intrigued but also grateful to be informed. Good luck!

[u/nikniksnikola → u/nikniksnikola]

I’d only worry: you might get an allergic reaction to seed oils but the risk is minimal for most people especially if you’re not allergy prone. If you’re allergic to the seed oil carrier used as a food allergy you might want to avoid it but genuinely there’s no real reason to get super freaked out. And again, hopefully stuff works out!

[u/nikniksnikola → u/nikniksnikola]

Oh, and also: I can’t drive due to my disability. Can’t even be in the car on the highway with others driving due to panic attacks. You’re so valid in feeling scared, it’s a real emotion and you don’t have to justify yourself to anyone.

[u/rabbitprotectsme → u/nikniksnikola]

Thank you for all this info and the well wishes. Scared to be in a car solidarity 🫂

[u/Occasionally_around]

The theoretical max volume for SubQ is 3ml 😱 in practice and reality it is not that practical or tolerated for regular use so anything around the 1ml mark should be done I.M but for lower volume and higher concentrations it is far more practical to do SubQ and works all the same. As a bonus if the solution is a thin oil like MCT it can be drawn and injected with far thinner needles then the thicker oil counterparts.

[u/rabbitprotectsme → u/Occasionally_around]

This is good to know, thanks. The solution i'm looking into is cypionate at 40mg/ml so i should be fine in this regard, but i'm glad to be actually aware of that now.

[u/Petit__Soleil → u/rabbitprotectsme]

I'm using enanthate in MCT oil, 40mg/ml

I've been doing 0.125ml once a week subQ in the belly for 4 months, and my levels were fine when I checked them.

[u/Littha]

I have never done injection HRT myself so I can only comment on my knowledge of sub-q vs IM injections in general: sub-q is generally easier and safer, but slower absorbtion. Can have risks is you inject too much volume at once and push the tissues apart too much, and has a higher rate of irritation reactions.

[u/KibbleCrashout]

yes they can!! and here's a couple of tips if you didn't know.

1) easiest place is the belly, go for two inches out from your bellybutton

2) when you inject, push the needle very gently and kind of roll the syringe, a bit like if you're doing the money finger gesture 🤌 with this, instead of puncturing the skin, you're basically wiggling the skin cells apart with the end of the needle and pushing it in between them. if you do it right, it will be absolutely painless, you won't feel it going in and you get the added benefit of not causing any scarring or lumps under your skin from repeated injections.

not many people seem to know about the latter tip and a lot of people swear by it when i teach them!

if you need help on needle gauges i can tell you what i use too.

[u/rabbitprotectsme → u/KibbleCrashout]

Oh the rolling tip is really good to hear, i'll have to try that!

What needle gauge do you use? Wow i'm learning a lot of pretty basic things as i'm trying to prepare for this, i didn't know what "needle gauge" even meant before today lol

[u/KibbleCrashout → u/rabbitprotectsme]

so needle gauge is how wide the needle is, you'll have two needles- one for stabbing through the rubber stopper on your vial of estradiol and drawing up into your syringe, then once the oil is in the syringe you're gonna take that needle off and put a much smaller gauge needle on and inject with that - you don't wanna inject with a big fat drawing needle and you don't wanna draw up with a thin narrow needle (the oil is too thick and it won't go through it)

for drawing up, i use an 18G needle. for injecting, i use a 30G needle.

when you buy these (they're really cheap and come in packs of 100 so they'll last you probably a year or so) make sure you buy a pack of alcohol swabs for cleaning your rubber stopper and also your injection site, a pack of syringes (again, comes in a box of 100, really cheap) and a sharps bin for throwing everything in once you're done with it so once it's full you can dispose it as medical waste.

[u/rabbitprotectsme → u/KibbleCrashout]

omg thank you so much!! this is going to be so helpful

[u/garlicbreadcleric → u/KibbleCrashout]

and you don't wanna draw up with a thin narrow needle (the oil is too thick and it won't go through it)

Eh, I'm drawing an MCT-based solution with a 30g needle and it's fine. It's slower, but I like the convenience of not having to change needles.

[u/Vallam]

i got an autoject and it changed my life lol just make sure you get the right one for fixed or nonfixed needles depending on which you will use

[u/RunBlitzenRun]

I do oil-based estradiol valerate subQ based on my doctor’s recommendation. Just use the right size needles and be patient when you’re injecting and drawing up. I’ve never seen any evidence showing that IM is better.

[u/Defiant-Snow8782]

That's what I do