Allergic Reactions to Insulin

GM Vs animal insulin

Choices – The Evidence
Evidence from people with diabetes
A little bit of history
Action and duration times of animal and GM ‘human’ insulins
Hypoglycaemia and loss of warnings
‘Dead in Bed Syndrome’
The concerns of patients are justified
Availability of animal insulins in the UK
Changing your insulin
What to do if your consultant refuses to change your insulin
Availability of animal insulin if admitted to hospital
Frequently asked questions
Allergic reactions to insulin


Allergic reactions to insulin

A bit of history
Allergic reactions to insulin have been around since it was discovered in 1922. It was estimated that around half of people using these impure insulins had allergic reactions – thought to be caused by the insulin molecule as well as the preservatives or the agents used to slow down the action of insulin, such as zinc. Until the 1970s only bovine insulin was available and this differs from the insulin our bodies produce by 3 amino acids and therefore is more allergenic than pork which differs by only one amino acid.

Localised allergic reactions are those that affect a specific area, such as rashes at the injection site, and the introduction of highly purified insulins reduced these localised allergic reactions to about 2-3% of people treated with pork or ‘human’ insulin.

Systemic reactions are those that affect the whole body and these are classed as very rare and can occur at the start of insulin treatment or many years after. In these cases the allergy is usually due to the insulin molecule itself rather than additives such as the preservatives.

Types of allergic reactions to ‘human’ insulin

There appears to be 3 types of allergic reaction:

First type – is the most common and is an immediate hypersensitive reaction. The symptoms vary in severity and start at the injection site with swelling, redness and itching but they may progress to the rest of the body. This reaction can be very difficult and even life threatening.

Second type – the main reaction shows as local tender subcutaneous [under the skin] nodules which develop 30minutes to 6 hours after an insulin injection. Inflammation of the lymph glands, a serum sickness reaction and arthralagia have also been reported. Arthralgia is generalised joint and muscle pains.

Third type – this is a delayed allergic reaction which usually occurs with insulin containing zinc.


  • Trying a different type of insulin.
  • Mild allergic reactions can be treated with antihystamines.
  • The treatment for allergic reactions to insulin which are moderate or severe is desensitisation. This involves repeating large numbers of injections of tiny amounts of insulin. This is known to be effective in 94% of people who are allergic to pork insulin but there are no such figures for people using synthetic insulins.

Just a thought…

The adverse reactions that people report with synthetic GM insulins have not been classed as allergic reactions but one does have to wonder if some of them actually are. For instance, IDDT has received many reports of the arthralgia type symptoms – joint aches and pains. These have been particularly noticeable in people using insulin analogues such as Humalog, NovoRapid, Lantus and Levemir. So is this the second type of allergic reaction described above?

We have also noted that these symptoms have been reported in people who have used ‘human’ insulin for 10 years or more – so is this a delayed allergic reaction?

As we know, these arthralgia-type symptoms could be a complication of diabetes itself but if that was the case, then the symptoms would not be expected to disappear after a change to pork insulin and many people have reported that they do! To add to this, people have also described the nodules and sickness [especially noticeable with Lantus].

So makes one wonder whether the adverse reactions some people experience to synthetic insulins have several causes, one of which could be an allergic reaction?