Better modern insulin pen color codes?

After nearly 40 years on insulin vials+syringes, I have recently switched to pens for both fast-acting and short-acting insulins.

Just a month ago, I mixed up my Tresiba and Humalog pens. I accidentally took 5 units of Tresiba as a bolus instead of the intended 5 units of Humalog and it was no big deal. My bg was way higher than I expected after the meal but when I went back where I keep my insulin it was immediately obvious what I had done and I took the correct Humalog bolus.

BUT if I had accidentally taken 17 units of Humalog instead of Tresiba it would’ve been a different story, 17 units of Humalog is a big deal.

The pens are both a dark blue.

Looking closer, the Tresiba pen has a bright green button that is slightly exposed. There are also some size differences and after taking the cap off I see the Tresiba has some green inside it too.

There are some dark red color accents on the humalog label and green color accents on the Tresiba label so I guess there is some attempt to color code.

Wouldn’t it be good, if there was a universal color code for insulin pens that was more obvious than “they are both nearly the same shade of dark blue until you look at the ends or color accents”? Like bolus and basal pen bodies being really strongly contrasting colors instead of different shades of dark blue?


Absolutely !!

I don’t use pens, but there should definitely be obvious, consistent indicator across brands. However, as someone with color blindness, color distinction is not always the best option.

I put a rubber band around my active insulin bottle to make sure I grab the right one.

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I actually thought the distinctly different colors of every pen on the market was actually pretty well thought out… those pens are strikingly different in appearance to me

Another thing that makes it easy is I keep a timesulin pen cap on the basal so I can check to see if I remembered to take it… bolus is easy to not forget since you take it when eating so it’s pretty routine… the timesulin cap is very different shaped than a standard cap

I take Fiasp and Tresibia. Recently Fiasp switched from blue/yellow to blue/red because of patient confusion. To avoid this I keep them in separate locations because it could be a dangerous mistake.

Old/New Pen colors:

In the dark or when not paying attention its easy to mix up the yellow and lime pens. Same exact body color / design.

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Great idea!
I use syringes and put painters tape around my fast acting syringe…yes I use them many times before getting a new syringe out.
I do the same with my vials as one has blue tape around it and is my fast acting insulin.
I color match! Lol.
Really helps me out.
Again your idea is great…wondering about color blind people?
It’s always something.

I use Pendiq digital pens and cartridges so had green pen for Humalog and Orange pen for Levemir/Lantus. Now only use fast acting insulin so no longer have the issue of a possible mix up.

I realized how bad mine was when 3 and 4 year old kids pointed out my mistakes when playing Candyland and other games. Especially in low lighting.

They should have Braille markings, as well, to take this idea to the full extent.


I’m back on syringes, I’ve never liked that they don’t give an accurate dose. I have to dilute all my insulin anyway. I have fiasp diluted to 1/3 of a unit and 1/4 of a unit, I put stickers on the diluted bottles telling of their concentration. I do carry a pen in my pocket when leaving the house on the off chance I may need it. Your right that those colors are dangerous.

I used to have my Lantus in a vial and my Humalog in a pen. The endo asked me why wasn’t I using pens for Lantus and I told her that keeping them different made sure I would never mix them up. It worked of course.

I know some people that have mixed up some big doses, I think it’s pretty common unfortunately.

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I keep my Tresiba in the drawer by the refrigerator and my Novolog in the drawer across the room. This works for me.

And my Novolog 1/2 unit pen is a solid bright red. It uses cartridges.

I use trulicity and tresiba I keep them in different places in the fridge. Plus the pen I am using,I keep in my insulin kit. Nancy50

I was going to make the same point, both about colour (or any visual indicator) not being the only distinguishing factor and about tactile indicators being a helpful way to distinguish things. I’m legally blind, so I actually depend on tactile more than visual. I find pens of different brands easy to tell apart actually. But pens of the same brands are identical (with the exception of Sanofi, who do include tactile markers on their reusable pens).

Ideally, pens in the same brand would have both obvious visual and tactile features that distinguish them. But I think pens of different brands may be more difficult since the companies probably aren’t communicating during product design.

It’s not braille, but the Sanofi reusable pens have good tactile markings on the end of the plunger to differentiate the blue and silver pens. But they are the only pens with tactile markings I’ve come across. The NovoPens I’m using now are totally identical except for colour (and the fact that one pen doses half units and the other pen doses whole units).

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Tresiba and novolog are made by same mfg and they’re easy to tell apart by feel. I can see well but I work in total darkness much of the time and have no trouble

Is that just because you have a Timsulin cap on one? Or are there tactile features that make the FlexTouch pens distinguishable from one another?

I’m on a pump break right now using Fiasp and Levemir and because I’m using the reusable pens, both the cartridges and pens are indistinguishable from one another without relying on colour, unless I were to add my own tactile markings or other distinct feature to one of them.

The Sanofi pens I mentioned above are distinct right out of the box, no need to add anything extra. Of course, the cartridges that go in them are not distinct, which might be problematic for someone who’s visually impaired.

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No even without the cap they’re completely different… the tresiba is bigger in diameter and the plunger doesn’t extend out from the pen when you dial it up… the novolog pen is much narrower and the plunger mechanism is totally different

Also novolog has two raised stripes on plunger button and tresiba is smooth…

Can you see enough to make out a picture at all?.

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Interesting…I think we must have different pens here. Both Tresiba and NovoRapid are only available in FlexTouch pens which, at least in pictures, look identical. When I search Google for “Novolog” pens (I think the US is the only country to call NovoRapid “Novolog”), it does come up with an different-looking pen (FlexPen)…

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Thats too bad… I like the flextouch for basal but i count the clicks both while dialing it up and pushing it in with bolus for a double check, which wouldn’t be possible with the flextouch (or humalog) design… I would not be pleased if my novolog was in a flextouch pen

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Yeah, that’s one of the things I hated about the FlexTouch pen. I prefer the reusable pens (NovoPen 5 and NovoPen Echo) so much better to anything disposable. You can get different skins for the reusable pens, and it would be nice if they made those skins with different textures as well as different patterns…

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Funny story… when we were just talking about the pen needle differences I was playing with them in my hand trying to describe them to you… I dialed up like 40ish units on the tresiba and forgot all about it—- which wasn’t obvious because the plunger doesn’t protrude.

Just now I went to take my basal and did the “1 unit” priming shot… except it was actually 41 units this time all over the floor. Thankfully i was able to halt it before it dumped the whole load and wasted it all

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