I reuse pen needles as long as they appear clean, no blood or not bent from the injection. I usually change them 1x a day. Using them for 3 shots. I put the cap back on them.
I find the insulin last just as long.
I change mine if I have extra needles in my pocket or my car if not I just make sure the cap is on good and reuse .
i always use a new one. my cde said always use a new one, the nurse i usually see said i could reuse them.
one more thing, adam, can i ask why you switched back to pens? ive only ever used pens but everyone is all gung ho on the pump. did you not like it? (im a bit reticent about having the machinery, kind of scares me).
I have been advised that if you can afford a new needle for each injection, use one. A used "dull" needle causes more scar tissue which over time can play havoc with insulin absorption.
what did you switch back from ? Just me being nosy as I am planning on switching to the Omnipod pump once it is smaller but the rep at the company said they are still awaiting FDA approval. But to answer the question, I always switch out needles. First because I get 500 needles for 3 months which is a bit more than 5 per day. Second because I use pen needles for both lantus and humalog and they are not supposed to be mixed and keeping them distinct would take me too much effort. The nano needles are so small but they do create a lot of litter. I don't know about how quickly insulin will go bad if you reuse needles sorry I'm not really a wealth of information besides my own experience.
When I was on MDI, I'd change the needle with each new pen. I reused needles for several times for years when I was doing injections and never had problems with infections or insulin going bad, or absorption problems.
I change once a day (three shots per needle). Lately, I've been doing an air shot of a couple units even when I don't change the needle just to make sure what I'm injecting is all fresh from the pen and not something that's been sitting in the needle -- probably unnecesssary, but I figure it can't hurt.
I change pen needles every time. With my insurance, they are cheap. My insurance company used to send me a hundred free with every insulin order, but that stopped. Still, I think it costs me $40 for nine boxes of 100 which lasts me a while changing every time.
Dr. Bernstein actually admits he reuses syringes until they get "dull." At his age, perhaps scarring isn't a concern. With pens, my biggest worry is that if you leave the needle on, you have a path to contaiminate your insulin. I've never seen any studies of the issue, so I think in the end everyone should just make their own call.