I'm assuming you mean, "Is there a refillable pen?"
All insulin delivery pens must be disposed of when thay are empty.
I thought the Lantus system used cartridges, meaning that you keep the pen body, but throw away the cartridge. That's as close as you get.
You cannot refil the cartridges.
Yep. Eventually it has to be disposed when it's empty just like the humalog pen. Ask your endocrinologist or pediatrition about it. If you have a humalog pen or other type of fast-acting insulin pen - don't mix them up! I've done it before - it's aweful. You just have to make sure you pay attention because they do look different.