We sell both, so we don’t have a horse in this race. But they’re built for different situations, and picking the wrong one usually means either paying more over time or carrying something you didn’t need.
The basic difference
A reusable pen is a metal body you keep. When a cartridge is done, you swap in a new one. Our V1, V2, V2 Pro and V3 all work this way, and there’s no limit on how many cartridges you can run through one.
A disposable pen is built around a single cartridge. You use it from start to finish, then the whole pen is done. Our Disposable isn’t single-use and doesn’t come prefilled. It just isn’t made to be reloaded.
Waste
This is where the gap is biggest. The best public numbers come from the insulin pen world, where both types have been used at scale for decades. They’re industry context, not measurements of our products.
- Plastic. UK NHS guidance says switching to reusable pens “can reduce pen-related plastic waste by 80-90%.” England alone produces about 60 tons of plastic a year from insulin pens, most of it incinerated.
- Parts count. A Sanofi design case study notes that a dedicated cartridge needs one plastic part, “rather than thirteen in a disposable pen.”
- Per pen. Novo Nordisk estimates each disposable pen sends 7 to 23 grams to landfill if it isn’t recycled.
- Carbon. An NHS project using Novo Nordisk data put disposable pens at about 15 kg of CO2 per person per year, against about 8 kg for a reusable pen expected to last five years.
The pattern holds across healthcare generally. A 2022 review of life-cycle studies found that switching from single-use to reusable products cut climate impact by 38% to 50% on average.
Cost over time
The NHS guidance describes the cost difference as small, “usually a small saving if pens are used for more than a year.” That matches how the math works: a reusable pen costs more up front, then each refill is just a cartridge. The longer you use it, the further ahead it gets.
If you’re only going through one or two cartridges, a disposable is usually the cheaper choice. Current prices for both are on each product page.
How long a reusable pen lasts
Major manufacturers rate their reusable pens for years, not months. NHS device guides list Lilly’s HumaPen Savvio at 6 years, the NovoPen 6 at 4 to 5 years, and Sanofi’s AllStar PRO at 3 years. A solid metal body with no battery doesn’t have much to wear out.
Every PepPen has a 6-month warranty, and with basic care (needle off after each use, wipe clean, don’t drop it) they keep going well past that. Our troubleshooting guide covers the habits that matter.
Convenience
Disposables win on simplicity. There’s no plunger rod to reset and nothing to reload. That makes them a good fit for travel, a short project, or a backup.
Reusables take one extra step at each cartridge change. In exchange you get a heavier, sturdier pen, more model choices, and the ability to run several cartridges through one pen. Swapping the cartridge swaps everything that touches the solution, so nothing carries over.
Quick guide
| You want | Pick |
|---|---|
| Lowest cost for one or two cartridges | Disposable |
| Something for travel or as a backup | Disposable |
| Lowest cost and waste over a year or more | Reusable |
| A sturdier, metal pen | Reusable |
| Twist-lock loading | V1 or V2 Pro |
Ready to choose? See the Disposable, compare the reusable models in our V1 vs V2 vs V2 Pro vs V3 guide, or use the Compare PepPens page.
All PepPens products are sold for research use only.
Sources
- Green Diabetes NHS: insulin pen devices (PDF)
- Royal Devon NHS: sustainable diabetes care (PDF)
- Sustainable Healthcare: SusQI diabetes project report (PDF)
- DCA Design: Sanofi TouStar case study
- The Medicine Maker: inside PenCycle
- Keil et al., Eur J Public Health 2022
- NHS BNSSG reusable insulin pen device guide (PDF)
