I am a pharmacist – this is a very important question to me. More important than you may realise.
I have lost you – I know – you don’t have the foggiest idea of what I am talking about. Even you diabetes experts aren’t on the same wavelength. So I had better explain.
Many of the insulin we use are suspensions – and they come in little thin tubes. Suspensions in thin tubes is not a good combination – particularly when re-suspending is so important for accurate dosing in patients with diabetes!
Look at one carefully and you will see balls – well the correct term is ‘bullets’. They may be made of steel or glass and they roll from one end of the cartridge to the other when you tip them up.
So you are now catching on – they are there to help in the mixing process. And it is important how many balls you have and how much they weigh.
I don’t have to tell you how important it is for the insulin to be properly mixed. The standard instructions are to roll the cartridge or pen between your hands and then tip it over 20 times before injection. You can see when the cartridge contents are re-suspended. So now stick the cartridge in a pen and you can’t see much at all. It suddenly becomes much more down to trust.
I then look at the patient – often older patients adding in their basal insulin for the first time. Occasionally one comment – “that’s all a bit of a pfaff” – and I realise that they are unlikely to follow these simple instructions. Call me a sceptic, but they happily count to 20 when I am with them, but what do they do at home?
If all patients followed these instructions they would be very likely to get an accurate dose. Obviously this may not be the case if they tip less frequently.
So your position is clear – you either push water up a hill – recommending 20 tips every time, assuming that the patient will follow your instructions.
Or – you choose a preparation with more balls and/or heavier balls and the patient is likely to still get an accurate dose with less tipping.
Personally I go for three heavy balls.