A primer on intramuscular bolus injecting

Totally agree! Absolutely no reason to have this restriction IMHO!

3 Likes

@Trying, try Amazon and see if they will ship to you!

2 Likes

Yes, I will do that. I could ask my endo for a prescription as well next appt. For some reason, she’s never offered to fill one on syringes, and I always forget to ask since I’m on OmniPod. I guess many use pens so Drs don’t provide prescriptions for syringes that often these days.

2 Likes

Pens are easier, but I still trust syringes more.

Sometime pen needles can get clogged, and even though you have depressed the pen button, nothing comes out.

I see this all the time when a pen has been in the fridge unused for a few weeks and I try priming it with the old needle in there.

With syringes, you see the movement and know whether or not the insulin has come out. If a syringe is clogged, the plunger doesn’t move!

2 Likes

Yes! I have Tresiba pens but have not used them. They’ve been refrigerated for monthss. I’m going to try to switch to Levemir vials on my next endo visit.

2 Likes

I don’t know if anyone else sees this, but if I leave a needle on a pen in the fridge for a few weeks, it gets totally jammed up.

2 Likes

What type of pen? I find this happens particularly with Humalog, but potentially with any pen if left alone for a long time regardless of refrigeration. Also if you remove a humalog pen tip but still have it, and try to reuse it (something I have done in moments where I went to change a pen after a tip bent, but then realized I didn’t have any new tips on me), if it’s been much time at all, you often can’t, because it hardens. I would not assume any pen tip that had been left unused (even if still attached) for even days would still be good without testing it, but testing with a unit or two is easy enough. If it is jammed, important to then prime the next tip well because extra insulin will have built up under pressure.

2 Likes

I have seen it mostly with the Humalog pens, but I have seen it sometimes with others as well.

I am now trying to always swap any needle that has been in there unused for a long while. It doesn’t seem to happen as much on pens that are in frequent use.

2 Likes

Yeah I mean, pens also get much less sharp with multiple uses, so while I def reuse mine, I replace them once they get noticeably more painful, and that seems to be well before they have clogging problems, but I use my pens daily. If someone uses pens rather infrequently (such as primarily pumps but every now and then needs a pen for some reason), I would probably say use a new needle tip each time.

2 Likes

Just catching up on this trail. A couple of years ago, after the aforemention discussion of clogging (hence unreliable dosages), brusing (on account of blunting) and air pockets forming (again giving unreliable dosage) i switched to single-use. I take the needle off the pen after each injection. It’s a faff, meaning i have to carry around needles everywhere i go, but realistically, if i’m ‘out of the house’ then unless i got something seriously wrong, i’m active and more likely to dive than to run high, so multiple injections unlikely. I can get away with one, and perhaps use for a second or third if really needed. But the needle is never on there for any longer than that.
Are you aiming to conserve needles to save money? Or to avoid the hassle of constantly changing? it would seem a false economy to me, but i guess each to their own.

1 Like

Thanks @Eric. Well, i thought that at first. But then i thought it through more… if i inject right into one of my ab muscles, and push the pen in deeply, i can’t see how it can’t enter the muscle, even at 4mm. There’s v little fat there, and when ‘pushed’ it is surely <4mm. If i fire the muscle, i can feel it right beneath my finger. unless i’m missing something physiologically, i think it must hit muscle.

But this brings me to another, bigger problem: basal injections, which is precisely where i DO NOT wish to hit muscle. I have been led to believe that injecting into the buttocks is the best place for this (slower absorbtion?) but i have very, very little fat there at all. i can’t really ‘grab’ any fat between my fingers, so feel there is a real risk that each morning and evening, my Levemir goes straight into my glute. How would this manifest, glycemically? A near-term (1-2hr?) BG dive, followed by a longer-term (4-8hr) slow rise? That’s what i’m seeing each morning, typically. (See below, last night).

I eat late (a problem in itself i know, but let’s assume this can’t be changed for now) and i could be getting the dosing strategy of my dinner wrong (i usually split the bolus), but below is typical, split dose or not. A 1.5-2hrs post-prandial hypo, which needs fixing with 5-10g carb, and then i steadily rise all night and am either awoken by an xDrip+ alarm at 9/10mmol, or awake naturally at 6:30/7am at a similar level. I can’t seem to get out of this cyclical rut.

Do you think this smells of a basal muscle hit? (Even with a 4mm needle?)

If not, i could try upping the night time dose, but i’m already at 15 at night vs 10 during the day, and daytime management seems okay. Not sure what else to try. Getting up at 3am each night to arrest a high is no fun.
If so, where else is good for basal injecting? I like to keep torso free for bolus rotation, but perhaps i will need to rethink this if the buttocks just aren’t suitable for me.

3 Likes

About Levemir - it does not matter how or where you inject it. You could inject it directly into your blood stream and it would not make much of a difference.

Levemir works differently than other basals. The other basals use complex aggregates of insulin hexamers to slow them. Those basals will slowly unwind themselves, which is how they implement their delay. But they are somewhat subject to effects of the site.

Levemir binds to the albumin of the blood and is slowly precipitated. It does not matter where you inject it.

This is what makes Levemir such a great basal. Even exercise will not affect its release, even if you inject it right into exercising muscle.

(Keep in mind, exercise will increase your insulin sensitivity, but it will not affect the RATE at which Levemir is being used.)

Reference:
https://www.nature.com/articles/0802746

Plasma albumin binding: a mechanism for buffering against variable absorption

In the circulation, insulin detemir is 98% albumin bound, and this property has been calculated to give rise to two potentially clinically important buffering effects. First, the absorption rate of insulin detemir is only slightly affected by variations in blood flow rate at the injection site. This is because the absorption rate mainly depends on the concentration difference of free insulin between the interstice and the capillary as insulin can diffuse both into and out of the capillary lumen. For human insulin, the capillary concentration is relatively high and flow dependent. A high flow will decrease the capillary concentration and increase the absorption rate. Similarly, a low flow will decrease the concentration difference and the absorption rate. In contrast, absorbed insulin detemir is immediately and almost completely bound by circulating albumin in the capillary lumen, so the free concentration is kept very low and albumin-bound detemir complexes are too large to readily re-exit the capillary. Thus, the free concentration difference effectively becomes more or less constant and independent of the flow rate.

4 Likes

Thanks @Eric - this is absolutely sensational info, and extremely interesting. thank you.

So in that case, i’m not sure what’s going on with my early morning highs and late morning lows, if they aren’t caused by a ‘skewiff’ Levemir profile.

3 Likes

Awesome post, @Eric.

BTW, on the topic of insulin pens getting clogged needles:. I’ve had it with all less frequently used pens, like those stored in the fridge with a needle. Levemir pens seem to clog more quickly than other pens for me.

2 Likes

Oh it’s purely re: convenience. There are times when just being able to grab a pen and take a shot with minimal fuss makes it much easier. I frequently take injections mid activities, like in a meeting, while walking down the street, sometimes while driving even… all less of an issue in COVID-times (and I’ve been changing my pen tips more frequently now), but in normal life, it’s definitely easier to not have to all of the time.

3 Likes

I agree it should work this way, but I have found a difference depending on where I inject it. I find if I inject in my arms or abdomen it starts quicker, I get a sharper peak and it doesn’t last as long as compared to my thigh, where it lasts longer and the peak is milder. I only use my thighs because of this and it is very consistent from day to day when injecting there.

It could just be whatever you are eating slowly creeping up on you through the night, combined with dawn phenomenon. If I eat late or eat anything high in protein and fat I will usually increase my nighttime Levemir dose to deal with it - I’ve found the effect can last hours, even when splitting the bolus or using Regular (Actrapid) insulin to deal with the delayed spike. One strategy might be to increase your Levemir but lower your second meal dose so that you don’t get the drop and the extra Levemir compensates for your digesting meal along with your basal needs. You might also consider taking more Levemir but taking the dose later so that Levemir’s mild peak isn’t coinciding with the peak from your mealtime insulin which may be happening.

3 Likes

I am currently 15u at night, 10u in the morning, which already seems unbalanced. This meal was late, low GI/GL carb-heavy and fatty (!), so perhaps i can combat with higher Levemir.
Do you think, in theory, switching to say 18u at night and 7u in the morning is strange/problematic? or seems a sensible way to deal with it, particularly since i am usually low in the later morning?

ignoring differences between injection sites, when does Levemir peak? and if i am generally too high at night and too low during the day, is potentially getting the doses to overlap (e.g. 11pm and 2pm, rather than 12hrs apart) a sensible strategy?

1 Like

Yes, absolutely. Don’t worry so much about balance, the beauty of Levemir is that at smaller doses it doesn’t last that long, so any overlap will be minimal but can be used to your advantage. I often overlap in the morning which helps greatly with dawn phenomenon and breakfast. I often don’t take my doses exactly 12 hours apart. Even if the morning dose is fading my basal needs are lower at bedtime and higher in the early morning hours. Any missing basal is usually compensated for by my dinner bolus or just by watching my CGM and taking another injection if it starts rising. Also even if it rises a bit, the fact that Levemir does have a peak will compensate for this later. Don’t think of it as trying to determine what your daily basal need is and splitting it according to a perfect ratio. Think of it more that your Levemir injection is going to give you coverage for approximately 10-14 hours depending on the dose, and that the dose you need is whatever your needs are for that night or day. If I were to eat a huge dinner of Italian food and dessert for example, I might take 3-5 more units of Levemir before bed than if I ate an early low carb meal. I don’t think about what I took that morning or what I want to take the next day, it’s mostly irrelevant. If I anticipate a stressful day at work or if I know I won’t be moving around much, I will take more Levemir in the morning to compensate. I don’t think about how much I took the night before. It won’t always be perfect but you just compensate with carbs if it backfires. As for the peak, it’s usually 3-6 hours after injection. It’s a mild peak and won’t be as noticeable if you have eaten a slow-digesting meal, but can help greatly with this. It can also help with dawn phenomenon, so if you find you are getting a rise at 3am every day, try to take the Levemir so that the peak is timed to coincide with that rise.

3 Likes

I agree with @Scotteric that the slow rise you see may be related to the meal you had previously eaten. I experience this, too. I’m on a pump now, so I usually set my dinner meal absorption rate at 6 hours. This helps with the early low (1-2 hours after bolus) and the slow rise, as Loop gives boluses distributed the absorption time (6 hours) to compensate for the food.

When I was on MDI I had the same problem. I was on Humalog (still am) and Lantus which I took every night at 10pm. I did struggle to resolve the issue you are experiencing, the initial low and then slow rise. To compensate for lack of an “extended bolus” on MDI (which at the time I had no knowledge of!), I kept my basal (Lantus) the same, but distributed my bolus over several injections for the meal. I know that may be difficult for you though since your meal is so late, and you actually may be sleeping during the rise. But that is what I did.

2 Likes