I’m a long time syringe insulin user (37 years) but a newbie (9 months) pen user. So forgive me for asking such basic questions!
If I am traveling for the evening and want to bring my pen with me and don’t want to have to fumble for the screw on pen needle: is it OK to screw the needle on at home, take the outer “space capsule” off the needle, leave the little grey cover on the needle itself, and then put on the pen cap over the needle, and then (many hours later) use the pen for a shot, and then leave the used needle on the pen till I get back home (again many hours later)?
Last night for the first time in 9 months I noticed that this seems to be physically possible. That is, I just noticed that if I take the space capsule off the needle that the pen cap seems to fit over it.
This is kinda the modern equivalent of “pre-filled at home syringe” something I had done for ages with plastic syringes. But I don’t know if leaving the needle on a pen for extended periods is bad in terms of air bubbles getting into the pen or who knows what other bad effects.