Injection devices have been around for centuries, and though the ubiquitous needle-tipped plastic syringe hasn’t changed much in the 60+ years of its existence, other technologies have been developed with significant advantages.

Though it’s tough to compete with a disposable product that costs just pennies to manufacture, this article will explore some of the disadvantages of the current standard that alternative delivery systems are trying to solve.

Before that, we should quickly define a syringe as the plunger/tube assembly, and a needle (or cannula) as the hollow tube often attached to a syringe. An injection sometimes is defined as the delivery of a drug with a needle, but in this article it means any method of delivering a drug. The epidermis is the layer of hard, flattened skin cells on the outside of our bodies, whereas the dermis is a layer softer, more active skin cells underneath. Subcutaneous tissue is a layer of fat and collagen, and finally muscles vary in depth depending on their location in the body.

The disadvantages of the needle-tipped plastic syringe are fairly well understood. Though they look simple, they require training to fill, choose a location, hit a specific depth, and dispose of properly. Without any bells or whistles, they are prone to causing needle stick injuries which occur millions of times per year worldwide, resulting in an estimated 85,000 HIV and Hepatitis infections (in addition to other diseases) annually.

Jet injectors (sometimes called needle-free injectors) have been around for decades, and use pressure to force the fluid into the body without any needle at all, resulting in less pain for most patients. Jet injectors can generally target different areas within the body, usually subcutaneous tissue or muscle, where some other forms of needle-less injectors can’t penetrate as deeply.

Unsurprisingly, these systems typically require a relatively expensive capital purchase followed by lower per-patient costs, though they still don’t seem to be cheaper than traditional needle-syringes overall. One of their main uses is in mass-vaccination, where their greater speed and simpler use are paramount.

However, jet devices have a history of cross contamination exactly for these reasons, and though many newer models have taken steps to address those concerns, one can imagine that any device built for fast mass administration is likely to have more risk of issues effecting large groups of people.

Other alternate delivery systems typically seek to not only solve the issues of traditional syringe-needle systems, but also the issues of jet injectors.

Injection Devices, Novel Systems and Their Characteristics:

Though each of these medical devices have their advantages, none solve all the issues without being significantly more expensive or complex to use than traditional syringes. The most likely way we’ll see these products widespread in the market is if they can reduce their price, or get insurers to pay for them by convincing the industry that less painful injections mean decreased healthcare costs long term.

System Type	Theory	Limitations	Advantages	More Info and Links
Classic Needle and Syringe	Penetrate into tissue with sterile metal cannula, disposable	Requires training to use, needle stick injuries possible, waste	Cheap and common, adaptable for various drugs
Jet Injectors	Penetrate into tissue with liquid	Cost, susceptible to cross contamination, wasted liquid	Fast, reduces pain
Microneedles	Break through epidermis with crystallized medicine, which then disolves	Shallow injection depth, only suitable for some molecules	Could be the cheap, painless, easy to use solution we need for some drugs	How do microneedles deliver drugs? Video
Nasal Spray	Deliver medicine to the bloodstream by absorption in the nose	Only suitable for some molecules	Painless and easy to use
Tiny Needles	Same as classic injection	Only suitable for some molecules, slow, fragile, still some pain and risk of needle stick	Fits current workflow
Local Cooling + Needle	Ice pack or electronic cooler near injection site numbs nerves	Adds time, cost, possible risk of cross contamination	Simple to add into current workflow	Local Cooling   Video
Local Vibrations + Needle	Vibration near injection site distracts nerves	Adds time, cost, possible risk of cross contamination	Fast and effective	Local Vibration Dental  Product
Local Mechanical Distraction + Needle	Distract nerves near injection site	Requires two hands, adds time, cost, possible risk of cross contamination or waste	Simple	Mechanical Distraction  Injection Relief Product
Suction Tip + Needle	Drawing up skin to syringe distracts nerves	Adds time, cost, possible risk of cross contamination	Fast and effective	Suction Technology Dermatological Product

Though each of these systems have their advantages, none are free of drawbacks or significant issues. The most likely way we’ll see any of these products widespread in the market is if they can convince the industry that they increase patient participation or decrease healthcare costs overall.

Tips for Considering Alternatives to Injection Devices

Don’t forget about the other hand! In many cases, the drug administrator either has plans for their other hand (pinching the skin, finding the right location, etc.) or can use their other hand to aid in the effectiveness of the novel injection device (smoothing skin, helping aim, etc.). To forget about the other hand is to forget the face of your father, as Roland of Gilead would say.

There is immense inertia for existing systems. Not only in comfort and understanding, but also in workflow. Novel injection devices or aids need to fit into this workflow to have a realistic chance of adoption.

Disposable is desirable. I’m the kind of guy who takes my soft plastics to the recycling center and grimaces every time I throw out my kid’s plastic disposable snack containers, but even I acknowledge the abundant proof that injection devices meant to be reused for multiple people introduce cross contamination risk and create a barrier to adoption.

The baseline is pennies. I don’t know what kind of deals huge medical organizations like governments get on syringes, but I imagine it’s in the order of magnitude of 10 cents each or less. Any alternative or add on will be instantly compared to this cost. It’s not really a fair comparison, given that syringes are mass produced in the 10’s of billions, but it’s the reality.

Though none of these novel devices has broken into the market in a big way yet,  they have a huge potential for human health – not to mention lucrative sales in the global market. Injection devices may not have changed much in the last hundred years, but hopefully the next hundred years will be a lot more painless.