The current adrenaline auto injectors (AAI) are pretty big aren’t they? Anyone who has tried to pack for a trip out will know, carrying two takes a sizeable bag. If you bring inhalers, antihistamines and other medication it’s a large bag!
“According to the Mayo Clinic, more than 200,000 cases of anaphylaxis occur each year in the United States. The World Allergy Organization estimates that up to two percent of the global population—as many as 150 million people worldwide—will experience anaphylaxis during their lifetime.”
The size of the problem and size of the current AAI devices causes a few challenges for those using them.
Are adrenaline autoinjectors even fit for purpose?
Are they even fit for purpose? They were originally invented for soldiers during the cold war as a quick way to combat chemical or nerve gas attacks, meaning they were designed for fit fighting men’s thighs, which would typically be much leaner than your average man or woman. Keep that in mind for later in this blog.
In the 1970s inventor Sheldon Kaplan recognized that modifications in the pen could turn it into a lifesaver for civilians, especially those susceptible to anaphylactic shock, where a fast response can mean the difference between life and death.
Philadelphia’s Solomon Solis-Cohen has been credited with being the first to try epinephrine on patients diagnosed with hay fever and certain types of asthma. Check out this fascinating article, A mighty pen.
Adrenaline Autoinjectors in the UK
Here in the UK we have three different adrenaline autoinjectors on the market:
- Epipen
- Jext
- Emerade
Over the years there have been problems with supply and shelf life, with some devices only having mere months to go before expiry, when they should last a year. However they are a life saver and give those at risk of anaphylaxis peace of mind and a fast acting medication should they need it.
But let’s look at other markets across the globe. I’ve just looked at two English speaking nations which also have a high prevalence of allergies: Australia and the USA.
Auto injectors in Australia
In Australia they have the Epipen (see images above for UK) and the Anapen. This works in a similar way, the black cap is removed and the white end is the needle end – clearly labelled in this image.
Auto injectors available in America
America has the Epipen, but interestingly they also have Auvi-Q, a pocket sized device with a needle inside that talks you through how to administer it. This is very innovative and would help people to use it. Panic can set in when using any needles and means people can make mistakes, inject their own fingers or lose the dose by removing the needle too fast.
- AUVI-Q®
- EpiPen® and EpiPen Jr®
- Epinephrine injection, USP auto-injector, authorized generic (AG) of EpiPen® and EpiPen Jr®
- Epinephrine injection, USP auto-injector, generic
- Epinephrine injection, USP auto-injector, authorized generic (AG) of Adrenaclick™
Not surprisingly the AUVI-Q is the preferred adrenaline injector in the USA. I’d love to hear from Americans who have used it, is it effective and easy to use? It’s smaller pocket size makes it much more versatile and easier to carry and the voice activation really appeals to me.
Are the needles long enough on Jext and Epipens?
There have been a few studies looking at the suitability of needle length of Adrenaline auto-injectors – ‘Longer needles needed to reach the muscle – by Rafael Ferrandiz, Ph.D. on March 17, 2016.’
Check out this article for more information Longer needles needed to reach the muscle
Summary: Intramuscular injection is recommended for fast adrenaline effect. The needles of some currently available auto-injectors are too short to reach the thigh muscle in many patients. Adrenaline auto-injectors with longer needles are needed.
I don’t want anyone to panic about this, there are simple practical things you can do. I got an ultrasound done on my own thigh and found my fat to fascia depth is border line. To get around this I would inject slightly lower towards the knee where there is less fat. You could also opt for the Emerade device (which I have myself) as this had a longer needle.
Experts will assert that the needle length is fine and we should not worry, but having explored this in depth myself, if you are female I would consider injecting lower on the thigh. I’ve certainly had times when I’ve used an Epipen and not felt any benefit at all.
What size injector is suitable for children under 12?
Epinephrine auto injectors – is needle length adequate? 2009
This study looked at a group of children and concluded: The needle on epinephrine auto-injectors is not long enough to reach the muscle in a significant number of children. Increasing the needle length on the auto-injectors would increase the likelihood that more children receive epinephrine by the recommended intramuscular route.
Make sure your child is moved up to the adult injector as soon as they a weigh 30 kg or more. Not all children are the same size at the same age!
What is the market size and growth for adrenaline autoinjectors?
I tried to find figures for the UK and will keep looking, but these stats from America show that it’s a huge market and also a growing one.
“The global autoinjector market reached a value of US$ 1.65 Billion in 2021. Looking forward, IMARC Group expects the market to reach a value of US$ 4.39 Billion by 2027, exhibiting a growth rate (CAGR) of 16.70% during 2022-2027.“
IMARC
What’s interesting is that the market for epiniphrine or adrenaline as we know it, is booming worldwide. Check out this report Epinephrine market is booming worldwide and also find out who the key players are. You have to pay for this report for a free sample is available.
It will be interesting to see which products we are using in ten or twenty years time, considering the limitations of the devices we use today.
Current challenges with adrenaline autoinjectors
There are quite a few issues, not just their size, which discourages many younger people and adults from carrying one, let alone two:
- Adrenaline autoinjectors are quite large
- Often devices are not carried at all times, instead left at home
- Not designed for purpose
- Often not used, even when carried
- Often not even prescribed when required
- Potential problems and concerns with needle length
- Lack of sufficient training in use
- Must be stored at appropriate temperatures
- Contain Sulphites, a known allergen
These life saving devices need a revamp in my opinion, so what is the future for adrenaline autoinjectors?
Check out this excellent article which takes a deep dive into all of the above issues: Adrenaline Autoinjectors.
Adrenaline inhalers?
Thanks to Rob, (commented below) I found out you can get adrenaline inhalers, called Prematine Mist. These can be bought online without a prescription apparently. It’s traditionally used to treat asthma but would possibly work for an allergic reaction? Any doctors out there who can comment?
I have heard that this is how asthma used to be treated, with an adrenaline inhaler, before the ones we use today. And interestingly, if you have a bad asthma attack and no inhaler, an adrenaline injection would help if you are desperate and have no access to other medication or medical support. Check out Prematine Mist.
Could we expect needle free and smaller autoinjectors?
From my research I think these much longed for devices are coming soon.
“What’s currently available is very effective, but we know it’s also underutilized,” says Dr. Jennifer Dantzer, a pediatric allergist and immunologist at Johns Hopkins School of Medicine in Baltimore.
Alternatives to the auto-injector may be on the way. Three pharmaceutical companies are developing new epinephrine delivery methods that are needle-free and potentially less cumbersome to carry.
This may encourage allergic patients to both carry epinephrine – and use it in a reaction. These are coming in the form of:
- Nasal sprays
- An epinephrine film that dissolves under the tongue.
These sound potentially really interesting and would be much smaller and easier to carry. Testing is currently underway in the US and UK with completion set for late 2023, but it could be a while before we see them being prescribed.
- Read: Is needle free epinephrine coming soon? – (US)
- Orexo’s nasal adrenaline rescue medication enters clinical development (US)
I couldn’t find any press releases of information about new products in the UK so would love to know if anyone has information about this. Drop a comment below or send me an email.
Needle free adrenaline injector
I also found this article regarding a nasal spray product – Zeneo needle free adrenaline injector . I’m unsure how fast these nasal sprays work and how effective they are at delivering adrenaline to where its needed. However I’m sure rigorous testing will be done, potentially it could work faster, be safer and easier to administer and carry.
This product has also been reformulated to remove sulphites, one of the Top 14 allergens in the UK. This solves a huge problem for people with a sulphite allergy due to all the current devices having this ingredient as a preservative for the epinephrine.
Read Intra-nasal epinephrine takes a step forward with Bryn Pharma.
What’s the future for adrenaline autoinjectors?
I’d love to hear your views on the future of AAIs. Do you carry two? Have you used them? Are you excited about the potential for some new more versatile products coming onto the market? If I had to choose, I’d go for the dissolving method as that seems so easy and could potentially be very small and easy to carry, and easy to administer. Please share your thoughts!
Have you or anyone else had any experience using the US product – curiously one you can buy without a prescription – of Prematine Mist – which is an old style inhaler for Asthma – though purposed here for Anaphylaxis?
There is some literature to suggest that it might be equivalent – though the usual disclaimers apply
Hi Rob, I’m based in England, UK so have only used Jext, Epipen and Emerade. I have used all three of these and all work in a very similar way. Pretty easy. So I’ve heard that old style inhalers did used to have adrenaline in them way back so maybe this is like that? It sounds like it would work. I will investigate this but don’t think we can get this in the UK. What country are you in Rob?