Needle length for using insulin syringes with Mounjaro pens?

[PuzzledObserver]

Just finished my first 2.5mg Mounjaro pen, 5mg pen on the way this week. Have bought extra needles and swabs to facilitate short dosing/extending pen usage - but also have a golden dose in my existing pen, and have had some thoughts about possible contamination risk if using a higher dose pen for many weeks.

So, thinking bout going the insulin syringe route. What length of needles do people use for those? The pen needles I was supplied with are 4mm, so that’s what I’ve bought more of to use with the pens. But are those sufficient if using an insulin syringe to extract the dose from the pen?

You can use 4, 6 or 8mm needles. I use 8mm ones as I find the length helpful when extracting. I haven’t tried 4mm ones. Logically they should be fine as the red seal isn’t going to be more than 4mm in depth I’d have thought looking at it.

You can get the same screw in needles from any pharmacy, then count clicks for partial doses. I think mine are 6mm. They won’t work for the bonus dose unless you keep twisting and manage to break the pen. I have some syringes from Amazon for that, although now that the new pens are only 4 doses they will soon be redundant.

I had wondered whether you need a longer needle for extracting. Do you feel any difference when injecting?

The needle itself feels the same, it's the gauge that would make a difference rather than the length. As long as the gauge is 30 or 32g then they will be just like the pen needle. It's easier to inject with a syringe as you aren't dealing with the more substantial pen mechanism which can be quite hard to push down.

4mm is fine, thats what i use