An update on splitting insulin pen boxes
top of page

An update on splitting insulin pen boxes

This guest post giving us an update on the back-and-forth with splitting insulin pen boxes is written by Megumi Howard. She is a licensed pharmacist in Japan and is currently in her last year of pharmacy school at Nova Southeastern University. Take it away Megumi!


Splitting insulin boxes has been an extremely confusing topic for community pharmacists. Before all this confusion started, insulin pens were dispensed based on how many pens would last for the corresponding days’ supply allowed by each patient's plan limitation.

When plan limitations were exceeded, pharmacies had to break up insulin boxes to provide the appropriate quantity or adjust the days’ supply to not break boxes. Pharmacies had different policies and procedures in place (or none at all) for how to handle this situation, leading to variation in practice.

After Walgreens was accused of fraud for falsely understating the days’ supply and reached a $269.2 million settlement, retail pharmacies quickly rewrote their policies and started breaking boxes to dispense a more accurate quantity of insulin. By the time we thought the argument was settled, the FDA decided to jump in and stir the situation up even more by requesting not to break insulin boxes for safety purposes.

So where does all this leave us?

Timeline of the issue

First, let’s go through the timeline of events so you can get the full background.

Prior to 2019: community pharmacies have their own policies

Community pharmacies created their own policies and procedures regarding breaking insulin pens. Some had a system set up not to break boxes, while others were dispensing the exact amount of pens by breaking open insulin boxes. Some pharmacies didn’t have any consistent policies and procedures in place, leading to variation among pharmacists working the same store.

Jan 2019: Walgreens is accused of falsely over-dispensing insulin pens

Walgreens had designed their pharmacy dispensing system to prevent pharmacists from breaking boxes, forcing them to alter days’ supply to fit plan limits. They are accused of civil healthcare fraud and reach a $269.2 million settlement due to over-dispensing insulin pens.

June 2019: The FDA requests pharmacies to dispense insulin pens in original carton

The FDA issues a “Safety-Related Supplement Request” to each insulin manufacturer requesting them to update Prescribing Information and carton labeling to specify that pens be dispensed in the original sealed carton.

Nov 2019: Package inserts and labels are updated

Manufacturers submit sNDAs and labels are updated (only for insulins, not GLP-1 RA). Now all labels state “Dispense in the original sealed carton with the enclosed Instructions for Use.”

June 2020: The FDA approves a single-pen carton

Semglee (insulin glargine), a long-acting human insulin analogue, is approved in a single-pen carton size.

Oct 2020: The FDA explains the risk of breaking insulin boxes

The FDA clarifies the November 2019 update advising against breaking insulin boxes. They note an increased risk of dispensing errors and of patients using the wrong product if individual insulin pens are stored or dispensed outside of their carton.

Insulin pens dispensed individually outside of their cartons may have contributed to medication errors, including wrong-drug and wrong-dose errors resulting in hyper- or hypoglycemia, missed doses, complaints of possible tampering, and dispensing without the instructions for use.



Master the future of medical writing and communications

Review of how to calculate days supply for insulin

Before we get into our best practices, let’s briefly review how to calculate insulin days’ supply, according to CMS:

Units per mL x the number of mLs to be dispensed = Total number of units to be dispensed

Total number of units to be dispensed / the number of units prescribed per day = Days' supply

*Do not exceed expiration date after opening

*It is recommended to prime insulin pens with 2 units prior to each injection. Priming the device is to ensure that the pen works correctly and air bubbles are removed, which improves insulin dose accuracy.

Best Practices

PAAS has put together a great update on best practices you can find here.

Here are some of their tips:

Dispensing multiple cartons

  • First, bill the accurate days supply (without breaking boxes)

  • If it gives you a rejection: reduce the number of cartons, recalculate days supply, and resubmit the claim.

Dispensing single carton or less

  • Use smaller size or a single-pen carton

  • If not available, call the patient’s plan for an override with accurate days supply

Be sure to document the following:

  1. Who you spoke to

  2. When you spoke to them

  3. Your initials

  4. A case number (if available)

If breaking the box is inevitable, make sure to consider the risk and incorporate additional safety measures

This can include:

  • Adding tamper-indicator tape

  • Providing a copy of the instructions for use to the patient

  • Labeling individual pens for individual patient use

The Bottom Line

- Try not to break insulin boxes

- Switch to smaller/single-pen carton sizes

- If you absolutely need to break boxes, take safety measures, like:

  • Adding tamper-indicator tape

  • Providing a copy of the instructions for use to the patient

  • Labeling individual pens for individual patient use

  • Document any conversations you have with the payer

NCPA has also put together a great presentation on calculating days' supply, including for insulin. I highly recommend you check it out!

bottom of page