How Many Days Will a Pen/Vial of Insulin Last?

Do you know EXACTLY how many days each pen/vial of insulin will last you?

Why not?

If you’re a part of this audience, you’re likely reducing carbohydrate consumption and taking a very consistent amount of insulin each day.

**If you're NOT yet reducing your carbohydrate consumption, please consider it. Following a low carb way of eating can make insulin usage AND blood sugar levels much more predictable, and for many, it's a way to reduce your overall insulin needs and make your insulin supply last much longer!

To figure out how long a pen/vial of insulin will last:

Take your total daily dose, add any extra insulin waste such as priming pens/infusion sets, then use that number to divide the number of units in the pen or vial that you use.

A 3 ml pen/cartridge contains 300 units of insulin.

A 5 ml vial contains 500 units of insulin.

A 10 ml vial contains 1000 units of insulin.

Did you catch that? ;) No problem.

Here's an example:

I use 7-8 units of Humalog per day from a pen, divided into 3 injections, which I prime with 1u each time.

8u bolus + 3u priming = 11u total per day.

300u per pen divided by 11u per day = 27 days per pen.

I currently have 14 Humalog pens, which will last me 378 days.

That’s more than a year's supply!

If you know how many days you can get from your current insulin supply, you will:

1. Make sure you’re getting enough insulin per month

2. Plan refills accordingly

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If you're in the USA and are having issues getting insulin refills, there are options.

Regular insulin is sold over the counter at most Walmart stores in the USA under the name ReliOn NovolinR for $25/vial and is also available in disposable pens for $45/5 pens.

(If you've been following here, you know that Regular insulin is much longer-acting than Humalog/Novolog/Apidra and is very well-suited for a higher-protein way of eating.)

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Please send a message if you need additional resources for lower-cost insulin

and how to use them. We’re here to help!

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