Guest Column | November 27, 2023

Human Factors Considerations For Your Emergency Use Drug Delivery Device

By Marcus Agunloye, head of human factors, Springboard

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Emergency use devices have been a long-standing part of the drug-device combination product market, with early autoinjectors being developed for military crisis applications and then adapted for general use to deliver epinephrine. From that point, the field has diversified, with the EpiPen leading the way for a range of intramuscular crisis autoinjectors, followed by the emergence of naloxone nasal sprays and autoinjectors for the treatment of opioid overdose, as well as subcutaneous autoinjectors for the treatment of hypoglycemia.

The development of these devices has led to many creative solutions to the use-related challenges experienced in emergency situations, but there is always room for further improvements, especially with the urgency of the opioid crisis. While many of these challenges are influenced by the device itself, they also require considering the wider landscape in which the device is used to deliver a fully realized product for the patient at the most critical time.

Who Is Using The Device?

Crisis treatment will always be an unpredictable context of use, where almost every element of the situation will likely be at least slightly different each time, but perhaps the most unpredictable element is the user themselves – who is going to use the device? Often, when looking at combination products designed for administration outside of healthcare environments, the patient is one of the key user groups to be studied, but in a crisis use scenario it’s likely that the patient’s condition will make it difficult – if not impossible – to treat themselves.

So, who takes over treatment then? Depending on the drug to be delivered and the situation at hand, it could potentially be a friend or family member who may have some knowledge of the patient’s condition; some form of caregiver, maybe a teacher or first aid provider; a first responder, such as a law enforcement officer or fire fighter; or, possibly most challengingly, a random passerby. This range of potential users poses a real challenge when trying to define and research user groups as part of a human factors engineering process. You can start with a baseline assumption that the user will know nothing about the device and how to use it, but this is complicated by the fact that some user groups will have received training, potentially on other devices that function differently. This introduces the risk of negative experience transfer, wherein a user applies their knowledge of one device or user interface to another, leading them to make use errors where functionality and use steps differ.

Where Is The Device Used?

Where is almost as broad a question when considering crisis drug delivery. Just as with the question of who, the answer is you’ll never know ahead of time – use environments will be widely varied. In this case, perhaps it is easier to design for the worst-case scenario – you can assume the user will be working in an unclean environment, likely with no resources outside of the information provided directly on the device itself and possibly with a high level of environmental distractions. These factors must be taken into consideration when designing a device, to ensure the device contains all the required elements and its use won’t be influenced by poor environmental conditions.

How Is The Device Accessed?

The who and where of a crisis device are challenging problems, and these two are combined in the next issue to solve: access. Where is the device and how does the user get it to the patient? In the ideal world the answer would be that the patient always carries the device with them, accessible for them or someone around them to administer. But we know the reality isn’t so simple – depending on the condition being treated, the number of patients who are likely to carry a device can range between many and none.

We have now seen a shift with epinephrine in some markets, with schools and some public spaces being allowed or required to hold non-prescribed epinephrine autoinjectors to be administered by trained members of staff. Similarly, but in a very different context of use, naloxone is being made available without prescription in many areas, in an attempt to make sure more devices are out there so that someone can intervene in the case of opioid overdose.

These types of access interventions are saving lives and when developing your product, it should be a key consideration of your research – how does it fit within this landscape? Does it need to integrate with current schemes, and should you be working to identify pathways other than the patient for your product to be distributed when it reaches the market?

Engaging With Patient Perspectives

The opinions and actions of patients should also be carefully considered in the development of a crisis device. Health conditions and treatments will always be a complex emotional journey for patients, and with many crisis devices this is amplified by the burden of continuous vigilance and always having to carry a device that hopefully never gets used.

In the case of epinephrine, this can be seen manifesting in a number of ways. The proportion of patients who carry their device with them at all times varies, particularly in the case of adolescent and young adult patients, who may be less likely to carry an autoinjector and more likely to engage in risky behaviours related to their allergy, making their risk much higher than in other age groups. To resolve this, you could aim to design a device that feels more consumer-centric and familiar-feeling to appeal to the patient, but there’s a careful balance to be struck in ensuring that users naïve to the situation can still identify it as a medical device, understand its importance, and then use it under pressure. Another expectation of the patient is to tell those around them – friends, coworkers, family – about their allergy and autoinjector. As simple as this sounds, this can still be difficult for patients who may be unwilling to share this kind of personal information.

Even more challenging is the situation with naloxone. Recreational opioid users can be resistant to treatment or even become combative after treatment due to the withdrawal effects they may face, even though receiving a dose of naloxone may be a lifesaving intervention for them. This may put potential users in a challenging situation, where what initially seems like an obvious action — delivering a dose of naloxone — becomes something that users may hesitate about or delay taking. Identifying and understanding these wider demands that are being placed on a user in a crisis situation is another important element to explore in the early stages of development.

These types of issues can be easily forgotten, especially when focusing on designing a device that is easy and safe to use in a crisis situation, but identifying, understanding, and trying to engage with patients’ and users’ broader issues with the condition and medication is another crucial tool in trying to ensure that the patient receives their treatment at the right time.

Address Information – And Misinformation – Directly

It is also important to consider the information that potential users may have been exposed to and how this may affect their attempts to use your device. With an injection device, user exposure to and experience with the EpiPen, the most widely seen crisis autoinjector, may lead them to make assumptions about how other devices may work. Negative experience transfer is a key factor to consider in the design process; teams must consider what existed before their device and how to design with this in mind. Then there is also the challenge of confusing and possibly incorrect information that potential users may have been exposed to in the media. Say “epinephrine” or “adrenaline” to a random person on the street and the first thing that comes to mind for many who haven’t been exposed to people with severe allergies may well be the famous scene in Pulp Fiction or even the irresponsible portrayal of delivering a crisis autoinjector into the heart and neck in Horrible Bosses.

Tackling The Challenges

So how do we respond to this dynamic range of challenges posed in the development of a crisis device? Effective research, user-centric design, and a well-considered strategy tying it all together are required for a successful approach. Research should ideally begin even before a product idea is conceived: If you haven’t talked to potential users before you’ve started defining the features and functionality of your product, then it’s possible that the wrong path has already been taken. Gathering as wide a range of perspectives and developing a thorough understanding of user needs and use scenarios from the earliest stage of product development always has been a cornerstone of user-centric design.

Design must respond to the needs of your user. Building on the information gathered from research, designs should be iterated, actively engaging with potential users through formative evaluations to ensure the device meets their needs and can be used safely and effectively.

Strategy is the final pillar. The final product could be perfectly designed – usable by anyone, anywhere – but if it isn’t in the right person’s hands at the right time, then its effectiveness in the field will be undermined. Building a proper understanding of pathways to device access and finding ways to engage and educate potential users has become a vital activity.


There are a wide range of patient- and user-centric challenges to consider when designing a combination product for crisis use. The keys to success in developing a new product for this type of this application are thorough research, user-centric design and properly integrated human factors engineering processes, and a strategic approach to ensure potential users can access and understand your device. With these steps, the next generation of devices can work toward both the direct use related challenges as well as the wider use scenario issues in crisis drug delivery.

About The Author:

Marcus Agunloye is a human factors engineer at Springboard. With a background in drug–device combination products, he is experienced in leading human factors programs and turning user insight into design inputs. Springboard is a Cambridge, U.K.-based engineering consultancy that specializes in development of devices for regulated markets, with expertise in medical device development, software engineering, and consumer product design and development.