Insulin Pen Cool Pouch Made From a Cool Bag and Duct Tape

If you're a diabetic like me, you'll always be grateful for the advances in care and medication (insulin pens and tiny needles for the win!), but there are some things that still prove to be a pain in the backside to work around. One of those things is keeping your spare insulin pens and cartridges cool while travelling - if it's out of the fridge for too long, it shortens the shelf life and you have to use it within a few weeks.

A solution to this is to put them in a cool pouch, which keeps the temperature down and protects them while travelling while also providing a handy container to keep them in when you bung them back in the fridge at the other end of your journey. I'm also using mine in the fridge to just store the spare pens in, as the cardboard box they come in gets damp and nasty, and loose pends and cartridges on fridge shelving is just annoying. It's also really cheap and easy to make, using an old (or new - they're not expensive) cool bag from the supermarket and some gaffer (duct) tape.

Step 1: ​You Will Need:

• A cool bag from the supermarket
• Gaffer (duct) tape
• A length of elastic
• A ruler
• A permanent pen (sharpie or CD marker)
• Scissors
• Your insulin pen

Step 2: Prepare Your Cool Bag

You'll need to cut the edges and unfold it to give yourself an nice, large sheet of material to work with. Make a note of which side is the inside of the bag (I don't know if this makes a difference, but better safe than sorry). When you've done that, you're ready to draw out your template. Decide on the size you want - it will need to fit your pens in and allow extra at the top for folding over to keep the cool air in. My finished pouch is 18cm x 10cm, with 2cm extra for the fold (this fits my Lantus Solostar pen and my Novo Nordisk NovoPen 4, other pens may vary in size). So my template would be 2 panels of 10cmx20cm, and 1 of 10cm by 15cm for the flap, all joined together to be folded, as in my scribbled diagram above. Use your pen and ruler to mark it out (I did mine on the inside, so I knew which side I was on), and then cut out around the edges with your scissors.

Step 3: ​Putting the Pouch Together

Fold inwards along all the lines to create the pouch shape, with the inside of the bag becoming the inside of your pouch. Then fold the securing flaps around so they're on the outside at the back, and tape them down with gaffer tape. Then you need to tape the whole of the outside of the pouch and the inside of the cover flap to give it some rigidity and a bit more insulation. In most of my pictures I've used basic silver gaffer tape, simply because the patterned stuff I used was going to make the photographs a bit hard to look at to see what was going on. You can go right in with whichever colour or pattern gaffer tape you want to here. Once you're done, fold the flap over so the end is almost at the bottom and then thoroughly crease the top. You'll find that when you open it again, there's a nice 2cm overlap of the main body that acts as an airlock.

Step 4: ​Adding the Elastic to Keep It Closed

You'll need your elastic to be twice the length of the width of your pouch. In this case, it's a 10cm pouch, so the elastic needs to be 20cm. Flip the pouch to the side the cover flap isn't on. Position your elastic so the main bulk is under the pouch, about halfway down. Then pull the ends up over the back, and tape them in place. Once it's in place, you'll want to cover the elastic to the edges of the back, and make sure it's secure. You could glue the elastic in place first, but the gaffer tape seems pretty secure, and you're not planning on using it as a one-string banjo.

You could also secure it shut with a couple of elastic bands instead of integrating elastic. Coloured ones would look pretty funky.

At this point, pop your pens in, fold over the flap and tuck it under the elastic. Job done!

Step 5: ​Some Final Notes

I'm going to add a disclaimer here that if you make this, test yourself to see how effective your pouch will be to account for differences in manufacturers of cool bags and the types of materials they use. I'd recommend using a plastic reusable ice cube and seeing how long it takes to melt. Diabetes medication is not cheap, and you don't want to accidentally ruin a pen load. Juggle your medication responsibly.

Testing with a pen straight from the fridge and my pouch at room temperature, my pen kept reasonably cool for a couple of hours. If you need to make it cooler for longer, try loading up your pens and keeping the pouch in the fridge for a couple of hours before travel, or slipping a couple of plastic ice cubes in with the pen - you can get shaped ones that are reasonably flat. I have some star ones that fit perfectly, but you can get other shapes that will work, too. Do a search for reusable ice cubes on Amazon.

Using a thicker/padded insulated bag would probably provide better cooling, too, but I didn't have one of those to hand. Again, this is why testing is a Good Idea™. If anyone tries several versions for SCIENCE™ before I do, I'd love to know the results.

Because it's in a couple of the images, and this is a post about helping diabetics, you should look into Insulcheck. It's a handy device that fits on your insulin pen and resets the timer each time you take your insulin so it's impossible to forget if you took it or not.