Lantus Pen isn't working?

This is a new one. My new Lantus pen doesn’t seem to want to inject more than a unit at a time. If I put pressure on the plunger, it will only click once. I had to let off the plunger and press it again 16 times to take my nightly Injection. I’m honestly not too sure how much insulin I even got after all that. I tried it with 3 separate needles in 3 different injection locations, so it’s not a scar tissue or needle issue.

What should I do about this? Can I get a replacement?

It sounds like you pen is broken. Something inside is physically broken. I have had than happen with a few pens. If you filled your prescription at a local pharmacy you should be able to take it in and show it to them and they should be able to replace, perhaps immediately. If you use a mail order pharmacy the process will likely be more difficult, but they should be able to replace it as well. Finally, if all else fails you should be call Sanofi and get some help.


If you cannot get a replacement, what I have done in the past, is use a syringe and pull the amount I need from the pen and inject it that way. I do that with pens any way because after it will no longer allow further dosing, there is usually another 25 units that can be retrieved from the pen, as there is more than 300 units in the pens. (I am very frugal with the insulin.) Hope you get this resolved.


If you don’t have syringes and cannot get an immediate replacement from your pharmacy you might also be able to get a pen from your endo to tide you over until the replacement process goes through.
Some years ago when I was using Lantus I got several pens that would jam and the plunger would not work unless you put a HUGE pressure on them (required two hands!). Needless to say, this was not compatible with safe pen injections and I got them replaced without a problem.

I tried bringing it back to my pharmacy, but was told that I’ll need to bring it up with the manufacturer. I tried calling Sanofi, but of course they’re closed.

I have 3 other pens which should last me a few weeks, but it’s still annoying.

Can you get syringes without a prescription? I know I can get pen needles, but do syringes have more restrictions?

That depends on the state in which you live. A number of states have changed their regulation of syringe access to make it easier for everyone (including those using illegal drugs) to get their hands on sterile needles. Some states have yet to adopt such actions.

This seems like a big-time brush-off. They sell you a product that’s defective (okay, the medication may be fine but it’s mechanically defective all the same) and they won’t replace it. You hate to antagonize your pharmacist, but I think I’d be insistent that it’s their problem to solve, not mine.

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If they won’t give you a replacement, then they should be able to provide you with some syringes. I am in Georgia, but when I was using vials, I forgot to pack syringes while traveling within the state, as a new diabetic I was a bit disorganized. The pharmacy I went to acted like I was a drug addict. It is legal in Georgia to buy them without a prescription. He really aggravated the heck out of me. I had to show my insulin vial to buy what I was legally entitled to buy without a prescription. Then he actually copied my driver’s license. I would guess that Sanofi will send you a replacement, but that doesn’t solve your immediate need. I am aggravated for you now. The pharmacy can certainly be recouped by Sanofi for the defective pen. Good grief, pharmacies should be more inclined to assist people with chronic illnesses that are managed with medications successfully.

Some states sadly have laws against medication returns (even warranty returns) at pharmacies unless the item was dispensed incorrectly by the pharmacist.

Update: I called Sanofi, and the lady on the phone had me prime the pen a few times and it magically started working. I wasted about 20 units, but at least it works now.

Wow, I had no idea. I’m sure there’s some (hopefully) well-meaning logic for this, but if that’s the case here, it clearly backfired.

@TimmyMac, glad you are back up and running with the pen. But if Sanofi were to do the right thing, they’d send you a new one without the glitchy plunger.