Probably all been said before inter manufacture insulin pen use

I use the novorapid pen to deliver Lantus

both are u100

I hate the cheap reusable Lantus pen prone to alter dose when delivering ( dial slips under thumb )
I decided to try the lantus cartridge in the novo rapid pen…


I looked closely at the cartridges

They are just about the same

The main difference is one has an orange cap on giving it a threaded section

underneath they are the same

a rubber bung inside an aluminium closure

They are both the same internal diameter

the both hold 3ml

Problem 1 - the Lantus has a larger external diameter and will not fit inside the novorapid pen

Solution 1 - It does when you take the label off!

Problem 2 - the lantus cartridge has no threaded section

solution 2 - remove one from a spent novorapid cartrige and put it on the Lantus cartridge

Problem 3 - the lantus is fractionaly shorter than the novorapid cartridge

Once you put the cartridge in the pen the internal clutch fitted to the plunger is not full engaged.

Solotion 3 - If you follow the cartridge with a small spacer it works fine!

The spacer is the coloured band used on replacement electric toothbrush heads

Problem 4 - the dosage may not be the same and the pen registers an availability that it may fail to deliver.

You can either deliver what it does and note the difference by reading the dial

or you can learn what it can deliver and change cartridges as appropriate.

Solution 4 - the dosage appears to be out by about 1/72 of a unit per unit - nothing to worry about

you will soon adjust your intake to account for what ever works for you

the number of given units is a personal thing anyway!

I am about to start with levemir and will get back with what is needed to do the same for it.


simply crack your non disposable pens open and put the cartridges into the appropriate reusable pen or make a modification like the one I do

I would not recommend decanting insulin even between 2 identical catridges!

I would be happier leaving it where the manufacturer put it and adapt the delivery method!!


I’m sorry I’m not following your post. Are you making a statement or asking a question? :thinking:

I have added bold bits does that help?

its a simple statement about the use of Lantus cartridges in a Novo rapid pen body

followed by a BTW

expressing an my opinion about the act of decanting insulin versus the use of disposable pen cartridges in appropriate pens modified or otherwise.