1 unit accuracy problems

I believe the manufacturer also instructs to change the pen needle every time. I didn’t comply with that direction. Just wondering now if doing/not doing a needle change has any effect on the withdrawn needle leaking a unit or two.

Could possibly allow air back in. I am going away from trying to do two doses with the same needle(same day). Just going to start wasting more to be safe.


This should take you to that site. If not, type in “Insulin pens dribble from the tip of the needle after injection” very detailed study of pens and drippage. Biggest item seemed to be getting rid of any bubbles.

1 Like

MDI person here. Great, informative thread.

When I was bolusing with small amounts, I used a Lilly Luxura HD pen, presumably named HD because it dials up in half unit increments. It is compatible with Humalog cartridges and I found it works well.

Like many here using pens, I do a single unit “air shot” except with the first dose on a new pen (which sometimes requires more), but @Terry4 is correct that the pen manufacturers say you should use 2 units between injections. You will go insane trying to get a PBM to include that extra amount on top of your doctor’s daily Rx, but that’s a story for another day, and one more reason why you should always have a scrip for more than you use.

I found with small daily dosage amounts I could easily do a 2 unit air shot between boluses because with a 300 unit cartridge, I still wouldn’t come close to using it all after a month or two, at which point I’d start to wonder about reductions in efficacy after the pen sitting at room temp for that long.

Thanks for the info, I have been streching the novalog past a couple of months but I always keep it in the refrigerator. Any comments on longevity if always kept cold?

If cold, certainly good until the listed expiration, but that’s a pretty conservative date, so probably quite a while after that. Most insulins are good about 30 days at room temp (at least)

Yes, I was going to mention the InPen, as it gives .5 unit doses. I’ve been very happy with it. I love how it tracks your insulin on board. Especially if you tend to take many small doses over the course of the day.