Needle size? And skin reaction?

[JurassicPark4Eva]

My first pen came with 0.25x4mm needles.

My second pen came with 0.23x6mm needles.

I had no skin reaction with the first pen and I'm having bad skin reactions with the second.

To be fair, I also inject Aimovig and usually have crap reactions with that and had much worse with Ajovy... However that responds well to hydrocortisone cream and this responds to nothing.

Is it possible it's the needle size / depth that's causing the issue?

Yes, I'm going to ask the pharmacist but I've only just sat down and looked at this and though I'd see if anyone had any insight!

It's possible it's the needle size/depth or brand (some coating on the needle). 0.23 is 32g and is a finer/thinner needle than 0.25 which is about 31g or 30g. I've only seen people react more to shorter needles 4mm and had to get longer ones 6mm or 8mm. So I wonder if it's the needle coating that's reacting to your skin? It could be either or both.

I've had a few needles from other providers that were more painful and stung while inside the skin and throughout the injection,but they were the same spec (32g×4mm) as the needles I have that don't affect me at all, just different brands. So it must have been something in/on those needles.

If the first one is better for you, you can order more 0.25×4mm needles online from the brand (if you can tell what brand it is - i used mine to do so), about 100 packs so you can use them regardless of the needles your other pens come with. That way you don't have to worry about needle issues from providers, plus you'll always have spare needles incase you need one.

For example this pic is showing a 0.25mm/31g needle. I'm not sure if they have 4mm or a box of 100 I think 90, but here is the link if you want to check.

https://www.medisave.co.uk/products/bd-viva-pen-needles-0-25mm-31g-x-8mm-box-of-90?

Here is a link to a 31g (0.25mm) x4mm pen needles, box of 100. You don't have to buy from them, you can shop around to find the actual brand you have. It's to show you the gauge (g) you need to buy because they tend to show them more often in guages than mm.

https://ukmedsonline.co.uk/products/4sure-pen-needles-100s-all-sizes?variant=45610581623010

For me it was

Novofine 6mm 31G - no reaction
BD Viva 4mm 32G - red and itchy
BD Viva 6mm 31G - red and itchy

Bought some Novofine 6mm and all ok again.

It may be a combination of needle length and brand although I have seen a few saying longer length has less reaction which makes sense because it takes the medication further away from the sensitive skin layer into the less reactive subcutaneous layer.

Really interesting, thank you both. I've found the original needles online, so maybe I just go back to them! I have one left over, so I'll do this weeks jab with that one and compare it with the last 3 jabs.

I’m getting this, two weeks running, I’m thinking I used to push it hard in but don’t any more, and it’s causing a reaction as it’s too close under my skin,

I’ve ordered some of the novofine ones, thanks to @WeAllHaveWings ,

Assuming your reaction is in fact caused by the needle and not the drug... It isn't the size that makes a difference - my supplier sends all sorts of makes and sizes. In fact longer needles can be an advantage because they put the drug further into the fat layer and therefore can minimise any reaction at the skin surface.

However needles are different. Some are coated to make them glide through the skin more easily, and in some people that coating causes a reaction. I also had a box of needles (BD Micro-Fine Ultra ) that caused a huge bruise every time I used them - they were a 4mm needle, incidentally. I don't know if I just had a defective batch or what, but I will never use them again.

I am currently using GlucoRX Carepoint Ultra 5mm and have had no issues at all with them.