Preservatives Added to Insulin

[duck]

I know these are controversial topics, but the crowd here seems to keep an even-keel and at the same time debate some tough topics:

To that end: does anyone know if the the "m-cresol" and phenols added to our insulins today are "safe" for us? Looking at the insert that comes out of my NovoLog box, there is 1.72 mg/mL metacresol in NovoLog, and 1.50 mg/mL of phenol.

Oddly enough, I only find two hits on these forusm about "cresol", but I was sure it had been brought up before...Google is my friend:

m-cresol / other insulin ingredients [Archive] - Diabetes Forums (http://www.diabetesforums.com/forum/lo-fi/t-10866.html)

Googling "m-cresol" will scare you, so wade in carefully. But what are the longterm effects of pumping/injecting this stuff into our interstitial tissues? And is there a way to get insulin without this stuff as an ingredient?

[Subby]

Duck, I am looking into this myself a the moment, having concluded from on-off testing that Novorapid, my best choice insulin, seems to be causing a bit of asthma and fatigue. There sure is a lot of fear mongering out there as you rightly point out, what is not clear is the real risks or problems of long term use that might be associated with these additives. I have been looking more into the potential sensitivity or allergy problem.

I did see a particularly negative blog about m-cresol, pointing to warnings of it as an almost carcinogenic which as I say without a high level of knowledge, strikes me as dramatic speculation at the levels we take. But it claimed that apidra has a lot more, which is interesting to me as I felt extremely sick on Apidra and barely got through a week. If I have a sensitivity to m-cresol, this might be an explanation.

I am guessing (and hoping) that the main problems are not so much long term poisoning/underlying issues, but sensitivities to one or the other, and what to do about it, I do not know as every insulin available to me has these additives - and that included bovine hypurin, before anyone jumps in saying this is another evil of synthetics and not animal insulins.

I am doing some more looking around, and I am also going to ask around about allergy testing for the components of insulin. I do know there is an Novo Nordisk allergy kit used to test for allergies, but whether this is an expensive, highly clinical type solution, I do not know but am expecting. My interest will be in testing other than that, phenol at least may have other methods to determine reactions. I will post if I get anywhere with that.

[duck]

Subby, I would be very curious to know if you find anything out. From what I can tell, m-cresol and phenol have a long history of getting added to insulin, back to the 1970's...Apparently, they are responsible for that intense "band-aid" smell that insulin has. So the safety of the additives seems to be well-established.

Still, I too wonder about what the options are if somehow it were determined that you had a sensitivity or outright allergy to any of these things...and I have always complained about being tired since I was diagnosed with this disease...Maybe I don't have a full-blown sensitivity to something in insulin, but *just enough* to make me slightly sick.

I know, I know. Pure speculation. But it would be nice to have options to experiment with and perhaps come up with a better treatment regimen.

[imac]

I am currently on novomix 30, which I dont think is available in the US ,it has a list of some 20 ingrediants some of which does not sound very pleasant. However the product leaflet states that they are inactive!

[jtausch]

when the ingredients sy that the are inactive that means it is not the stuff thats works in your body. It is just the medium that the insulin/ medicine is carried in

[imac]

Yes I am not too sure about the phenol, we spray fence posts with it to stop the white ants eating them.

[REDLAN]

What matters is the dose and not whether the chemical itself is toxic. ALL chemicals are toxic in sufficient quantities - there have more than a few deaths in ecstacy users from drinking too much water.

All chemicals (including drugs) have a dose response curve. The curve is typically "S" shaped. What matters in toxicology is the threshold - i.e. the point at which the chemical starts to do harm.

Our bodies tolerate small amounts of toxins and carcinogens all the time. These chemicals are either excreted in the kidneys, or turned into less-toxic products by the liver.

Insulin has preservatives added to it, because to the average microrganism insulin is a protein energy shake. Every time you push a needle through the rubber cap on the bottle you will also push some bacteria into the bottle. The preservatives are there to prevent those bacteria from multiplying.

In the case of insulin what matters is the concentration - if the concentrations of phenol were the same as in fence paint, then yeah I think we might just have a toxicity problem.

[REDLAN]

As Subby points out the issue with the preservatives added to insulin is the development of allergies to the product. Once the body has become sensitised to an allergen, then a reaction can occur at very low concentrations. In most cases the person will get a rash after taking the medication - you will find this warning on your medication description. In very severe cases the person can suffer from anaphylactic shock.