A number of important studies have been conducted recently which relates to the inadequacy of the Epipen’s needle length when applied by certain types of patients who are suffering from anaphylaxis
Put simply the adrenaline from any adrenaline injector must be injected into a muscle. The problem is that the needle has to first pass through a layer of fat and for some people with a thick layer of fat, the needle simply does not penetrate sufficiently to reach the muscle. For over a quarter of women the Epipen needle length is not enough.
At the moment most auto-injectors have a needle the same needle length – around 15.2 mm – and in a recent study it was shown that of 100 patients, 19 patients were shown to have a fat layer greater than 15.2 mm and without exception all those 19 patients were women. The study goes on to show that some 28% of women are at serious risk of their adrenaline not being appropriately administered because of the higher than average levels of fat on their thighs.
In the US the recommended needle lengths for new borns are 16 mm, children between 1 and 12 years old 25 mm, and adults from 25 mm to 31 mm. In the UK the Resuscitation Guidelines recommend a 25 mm needle for all ages.
The Epipen and Jext autoinjectors do not meet the UK Resuscitation Council Guidelines with their longest needles being only 15.0 and 15.4 mm respectively. Insofar as needle length is concerned there is only one adrenaline auto-injector that appears to meet Resuscitation Guidelines – the Emerade.
Patients, and women in particular, should therefore make their prescribing doctor aware of these issues and insist that needle length be taken into consideration when prescribing their auto-injector.
This is an update to a blog I wrote in 2013 which lamented the fact that the adrenaline autoinjector models in the market (Anapen and the old Epipen model) carried needle lengths that might not deliver the adrenaline which an anaphylactic patient might need.
Two years later Anapen has disappeared from the market and Epipen has a brand new model, In addition two new autoinjectors have arrived in the UK, Jext and Emerade. Most people simply get a prescription from their doctor and get what they are given in the chemist but, just like buying a new pair of clothes, you should consider your choice of this life saving device very carefully.
We rarely question our prescribed drugs as they are taken orally and who are we, the unqualified patient, to question the choice of drug. In the case of these autoinjectors we should not question the life saving adrenaline but we should question the delivery method – the choice of autoinjector.
In a series of blog posts over the next few weeks I will be reviewing these three autoinjectors insofar as the following features are concerned:
- Needle Length
- Shelf Life
- Ease of use in an emergency
This website has no affiliation or personal interest with any of the manufacturers. I just want to make sure that all those with a serious allergic response leading to anaphylaxis have an effective autoinjector to hand and realise that these three delivery methods are not the same.
As consumers, we also have a choice!
David I Glaser
If you are even being considered for venom immunotherapy in the UK there is the probability that you have been stung be a wasp or bee. You may also have suffered a severe life threatening allergic reaction called anaphylaxis. You will have been tested for which particular insect stung you – in the UK that is normally either the common wasp or bee – and then you will typically hear something like this from your doctor:
“I think in the circumstances it would be very sensible to start a course of venom immunotherapy to sort this problem out.”
The patient may ask a few sensible questions whilst the “bear in the room” question is this:
“Given that a sting nearly killed me in the not too distant past, is it not complete madness to volunteer to be stung artificially for the next three years?”
The answer I would always suggest is simple: Venom immunotherapy given under the strict guidelines as practiced here in the UK on the NHS and as described in the BSACI Guideline on Venom Immunotherapy is very safe. There are of course risk factors associated with certain conditions but the risks associated with having no treatment and then being stung in the middle of nowhere far outweigh the risks of the treatment. Logic dictates the treatment!
However logic does not always rule the day but rather our individual psychology and mindset.
In my non-medical experience of listening to many hundreds of patients faced with the dilemna of having the treatment or not, I think the great majority see the wisdom of having the treatment. However it is also my experience that most of us opt for the treatment because it psychologically gives us control over our lives again. The big gain of the treatment in my opinion and theirs is the psychological reassurance that there is more certainty over our lives once again and we have taken control and are doing something about it.
In contrast those more relaxed patients with a different mindset who feel more comfortable just going with the flow of life and taking a view on the future will typically get on with life and simply deal with the next sting by way of an adrenaline injector if, or when, it happens. For the control freak like myself I can only look at those folk with genuine admiration – I wish I could be so calm about the future.
I am now the other end of the immunotherapy treatment and hopefully desensitized to the dreaded wasp – can’t be certain however, still carry my adrenaline injectors, and so retain some form of notional control over the situation.
I can’t ever see myself being able to give them up.
David I Glaser
Once again as the wasp sting seasons comes to a peak here in the UK the media are full of articles about the problem our citizens face. Whilst much of the article I came across in the Daily Mail makes sense (especially the fact that wasps do have a a very important ecological function) it must also be declared that once again they are peddling the myth that vinegar helps in treating wasp stings.
Please see the page on my own website which talks about the different treatments which people suggest work fantastically – these include vinegar but the sheer variety and mass of treatments probably means that psychology and rubbing is much more important than the actual ointment or product applied.
David I Glaser
David Golden, MD, one of the world’s top allergy specialists in insect venom allergy, has recently written a paper for the American College of Allergy, Asthma and Immunology (ACAAI) which argues that insect venom allergy is definitely on the increase affecting around 5% of Americans.
We are not here just talking about local reactions but rather the more dangerous systemic reactions which can of course lead to death – and he argues that it is important that it is treated before the next reaction. The treatment is venom immunotherapy, detailed elsewhere on my website, and we strongly concur with David Golden in this area.
So, if you have ever had a bad systemic reaction to a wasp or bee sting, then go and see your doctor because there is an effective treatment and, if you are a UK citizen, it is absolutely free on the NHS!
Author; David I Glaser
Horse fly Image,link courtesy of the Daily Telegraph
I was very sad to read in this article of the very sad death of a 48 year old Englishman, Andy Batty, arising from a serious allergic response, or anaphylaxis, to a horse fly bite.
This is very unusual – in fact the very first time I have heard of this serious allergic response to a biting insect.
It is important to appreciate that a stinging insect such as a wasp or bee injects venom into the victim and this is the type of insect encounter that typically generates anaphylactic shock. In contrast, biting insects such as horse flies and mosquitos inject a tiny bit of initial saliva into their victim and then suck like mad to extract nutrients from their victims. Often there is no meaningful introduction of any insect proteins into the victim and hence typically no serious allergic response.
We should not be alarmed by this event but just rather saddened by the terrible damage a tiny insect can do to a six foot rugby player and both his family and friends.
Author: David I Glaser
I know I may seem to go on and on about adrenaline auto-injectors, BUT they really worry me. These are life saving products and it is important that they work when they are used for whatever allergic reaction may happen.
So my interest in this article concerns needle length.
It is really important that the needle injects its life saving drug into the muscle of the thigh and a study in 2009 indicated that in fact a significant proportion of children did not have a long enough needle to reach the muscle the skin and fat. The same is undoubtedly true of adults because we all have different size thighs and yet the manufacturers of the auto-injectors provide a “one size needle fits all” solution to patients. Surely at the very least the length of the needle should fit the needs of the patient?
So if you have a large child or are a larger than normal adult and require an emergency adrenaline injector, such as an EpiPen, Jext, or Anapen, then please talk to your doctor and let us start putting some pressure on the manufacturers to provide the right solution for all patients and not just for some.
In short not only do we need different size of dosages but we also need different size needles, an option that is currently not available.
Article by David I Glaser
Well done to the Anaphylaxis Campaign on developing its excellent pdf on how to cope with having a severe allergy to wasp, bees and other flying insects. You can find it on this link and are recommended to download it and print it out for a good read offline.
There is of course a lot more information on this website but it is nevertheless helpful to have a crib sheet to take away with you!
Well done to my friends at the Campaign for this document!
by David I Glaser
I am getting an increasing number of worried enquiries about how best to store adrenaline injectors in warm or cold climates. Does heat and cold make our Epipens, Jext and Anapen injectors inactive and potentially life threatening?
The manufacturers do have guidelines but they are fairly useless for the real world.
EpiPen say “You should take your EpiPen Auto-Injector everywhere you go, but it should be kept at room temperature (25°C, 77°F) until the marked expiration date, when it should be replaced” . Just how is someone meant to keep their EpiPens at this precise temperature and surely a range of temperatures would be more helpful. In their advice to professionals (not patients) it says:
“EpiPen and EpiPen Jr Auto-Injectors should be stored in the carrier tube provided at a temperature of 25ºC (77ºF); however, temperature excursions between 15ºC and 30ºC (59ºF to 86ºF) are permitted.”
Just what is a temperature “excursion” and how long does an excursion last? Suppose the safe temperature is exceeded? Are patients never allowed to go to the beach or play in the snow and just how are patients expected to maintain this temperature range?
Finally, why is the advice to professionals different to advice to patients?
David I Glaser