MommaOfMuse said:
Honestly I don't know...remember I have a Lev Kitty...my Lantus boy only needed 2 shots, so I am just going by what is listed in the stickies over on the TR board. I think it is probably because it can eat into the silicone coating inside the syringe...but I really have no clue. Other than I know that Lantus is an acidic base and Levemir is a neutral base.
I know a few have capped a filled Lantus pen when they have had to shoot late for various reasons like a hiding cat, or stalling a shot...but I know it isn't recommended for long period of time.
Mel, Maxwell, Autumn & The Fur Gang
With me ithe prefilling is for two reasons - one is to make sure I don't forget it in the evenings - and because after a long day at the office staring at small print - its tougher to see the markings. I know the manufacturer doesn't recommend prefilling - but then again, they say its only good for a month, and most people seem to be managing just fine for a lot longer (thank heavens cause my vial was 160 dollars).
So I'll have to do some research - thanks.....
Em
I think I found it - the ADA did a study a while back on the life of various human insulins
http://care.diabetesjournals.org/content/26/9/2665.full
The important part (and where I think the sticky came from) is here - and the bottom line is that prefilled, refrigerated syringes became turbid after two to three days depending on the syringe used. It actually looks like the Lantus still met specifications in all but the Walgreen syringes, but I don't think anyone would shoot cloudy insulin -I know I wouldn't.
"The stability of Lantus when it is prefilled into syringes and stored up to 7 days was evaluated using four different types of syringes (Aventis, data on file). The following syringes were tested (200 syringes of each type): 1) BD Ultra-fine, U-100, 0.5 ml, 30 G ×½ inch (Becton Dickinson [BD]); 2) BD Ultra-fine II (short needle), U-100, 0.5 ml, 30 G × 5/16 inch (BD); 3) Walgreens super thin syringes, U-100, 0.5 ml, 29 G × ½ inch (Walgreens); and 4) Reli-On insulin syringes, U-100, 0.5 ml, 30 G × 5/16 inch (Wal-Mart).
The syringes were stored either at 41°F (5°C) or 77°F (25°C) for up to 7 days, after which the Lantus solution was tested for filtration time, byproducts, insulin glargine content, and m-cresol (preservative) content. The Lantus solution was visually inspected and pH measured every day (except days 4 and 5). Microbial contamination was not evaluated in this study.
Results Visual appearance at 41°F (5°C).
The Lantus solution became turbid more quickly in the Walgreens syringes compared with those of BD and Reli-On. By day 3, the Lantus solution was turbid in all four syringe types. After 2 days of storage in the Walgreens syringes, the Lantus solution did not meet specification."