Toxicity of insulin due to phenol and metacresol

[Wannabeflatliner]

Hello,
Bumping this thread as I am researching lately effect of metacresol and phenol in insulin on our body.
Here are the different metacresol concentration depending on the insulin you use :

NovoRapid and Fiasp	1.72 mg/ml
Humalog and Lyumjev	3.15 mg/ml
Apidra: Approximately	2.8 mg/ml

Now I react to the insulin preparation of humalog (local skin redness/itchiness/inflammation) because of the higher concentration of metacresol but I do not react to novorapid or Fiasp.

I have looked at other solutions to keep using Humalog and Luymjev (Luymjev being the fastest insulin on the market at the moment). They both come in U100 and U200 concentration. Both of them have the same concentration of metacresol. I was thinking if we use U200 formulation, and mix 50% normal salin and 50% U200, we could have the equivalent of U100 insulin but with half the concentration of metacresol!! I dont know if this has been tried already.

I did find an article where they mixed insulin with normal salin in an insulin pump for a child with minimal insulin need, so mixing with normal salin seems to be feasable (Article named : Use of Lispro Insulin Diluted with Normal Saline to 10 U/ml in an Insulin Pump: Case Report) ... I don't know if anybody has experience with that?

 

[EllieM]

Hi @Wannabeflatliner and welcome to the DCUK forums.

I think the article you refer to is https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3570861/
though now you have made 5 posts you should be able to add your own links.

There have been a few threads here about people with allergies to the preservatives in insulin

Allergic to all insulins

Hello; I am type 1 for 39 yrs and live in US. I am allergic to all insulins since starting on pork back in 1983. Then I was switched to Humulin and felt very ill on it. Switched back to pork and remained on it for 25 years despite not feeling well from it. Tried to switch to Novolin products...

www.diabetes.co.uk

The link to Dr bernstein's video and desensitisation might be of interest.

But honestly, in your position I'd probably stick with the novorapid or fiasp and prebolus a bit more.

Have you discussed your issue with your diabetic team? You'd obviously need an OK from them to try diluting the U200....

 

[Wannabeflatliner]

Hi EllieM!
Thank you for the warm welcome! Yeah I did stumble upon some information on desentization aswell! Pretty interesting.

For the moment I am sticking with Novorapid and hoping it will stay all right! I was discussing more of theoretical concepts! Not sure I am ready to try fancy solutions such as home made mixes at the moment

 

[EllieM]

It's a shame that insuman is no longer manufactured, as that had no metacresol. Apparently in the past insulins used one preservative or the other, so you could swap between them if you developed an allergy. Now they all seem to have both.

Not sure whether a compounding pharmacy would be able to brew up the mix if it were to be approved by a specialist?

There's an interesting article about desensitisation, which mentions that all commercially available insulins contain metacresol

Successful management of allergy to the insulin excipient metacresol in a child with type 1 diabetes: a case report

Insulin allergy to human insulin preparations during the treatment of diabetes is suggested to occur at rates ranging from <1.0% to 2.4%. These reactions vary from mild localized reactions, which resolve with repeated exposure, to life-threatening ...

www.ncbi.nlm.nih.gov