How long to let new Lantus pen sit out of fridge before injection?

Hi everyone!

How long should I let a new Lantus pen sit out of the fridge? I took one out about 45 minutes ago to use tonight and I held the pen in my hand for 5 mins or so to warm it but let it sit on the counter for the rest of the time. How long would you say it needs to sit out for before I use it? Thanks everyone for your help!

Update: I wound up taking it an hour and 15 mins after I let it sit out. Didn’t hurt or feel any different at all so I assume that was good enough. Tomorrow I’m going up on my amount by 2 units. So far so good! Right now I’m at 11.

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There’s no real rule for this. Just let it sit out until it’s about room temperature/not super chilly. I usually hold the insulin in my armpit/under my knee for like 5 min and then inject.
Besides stinging a little, cold insulin won’t really do anything to you.

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This sounds counterintuitive but once opened most of but all insulins - including Lantus - can be kept at room temperature for 28 days. There’s no harm in injecting it cold but using room temperature lessens the air bubbles you withdraw if you use a vial.

That said, always check the storage instructions for your particular formulation.


On the Lantus website, it said in big letters, ‘NEVER USE COLD INSULIN’ so I assumed it was dangerous! LOL Thanks for that.

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That’s weird. I never let mine sit out, just use it straight from the fridge. No issues. I keep mine for months and it never loses potency (I use a vial and syringe, not pens). My cynicism tells me that perhaps they say never to use cold insulin so that people will keep their vials out of the fridge so they won’t last as long. I can’t imagine another reason, and have never had any issues. I don’t even notice or feel the temperature when injecting. Hope that helps.

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Once opened they can sit at room temperature and should be discarded after 28 days. It should say that on the prescription bag from the pharmacy. If you’re unsure you can ask the pharmacist.Does your health care provider have an on call number for after hour questions? Or someone in endocrinology that can answer your medical questions? I can tell you that my son was recently diagnosed with type 1 diabetes and I have called during business hours and after business hours with dosing questions. It can be tricky. Good luck!