Bad Insulin? How Know When to Toss it Out

Insulin Safety Tips: When to discard insulin

When in doubt, throw it out!  Discard insulin that has been:

  • Violently shaken or dropped.
  • Has a change in appearance (Regular, Lispro, and Glargine should always be clear but NPH, Lente, UltraLente and 70/30 should always be cloudy).
  • Is stringy or has clumps.
  • Has any solid particles floating in it or stuck to the bottom.
  • That has been frozen.
  • That was exposed to temperature extremes like being left in a car or in the sunlight.
  • If the latex seal is damaged when you open a new vial, or if you damage it yourself.
  • If you accidentally inject one type of insulin into another (vial) of insulin.

What should insulin look like?

According to BD Diabetes. There are two ways to tell when insulin is no longer good: poor performance and unusual appearance.  Visual inspection of your insulin is important — each time you use insulin be sure to check its appearance. If you begin to have episodes of hyperglycemia, your insulin may be bad.

  • Regular, Lispro, and Glargine should always be clear.
  • NPH, Lente, UltraLente and 70/30 should always be cloudy.

Insulin should never be thick, clumpy, stringy, discolored, or have solid floating particles, or solid residue at the bottom of the bottle (vial).

How long does insulin (bottled) last? What is the “shelf-life” of insulin?

  • Unopened insulin, that has been refrigerator is good until the package expiration date. Once insulin has been opened, even when it is refrigerated, you need to use it or discard it within 28 days after puncturing the seal with a syringe.
  • Unrefrigerated insulin (stored at room temperature) is good for one month.
  • Never freeze insulin or expose it to heat (like leaving it in a car, bathroom, or sunlight). Once exposed, assume the insulin has been damaged and discard it.
  • Insulin that has been dropped or shaken can also be damaged.  If it turns cloudy or your blood sugars run higher than expected, discard the damaged insulin.

How long does insulin stay “good” in an insulin pump cartridge?

Under normal conditions, insulin in pump cartridges may last 3 to 5 days. However, some Humalog users report (Diabetes Mall)(2) that it should be changed at least every 72 hours to avoid unexplained hypergycemia (high blood glucose). It is safer to simply change your cartridge when you change out your site.

If you go swimming or to the beach, or unhook yourself from your pump for activities, make sure the pump is stored in a cool, dry place (like under a beach towel in the shade). Exposure to sunlight and heat will damage the insulin in the cartridge and you will need to replace it.

How long does insulin stay “good” in insulin pen cartridges and prefilled pens?

The shelf-life and viability of insulin in OPENED cartridges for insulin pens and prefilled insulin pens ranges from 7 to 30 days. Be sure to read your prescription instructions and labeling information.

1.5 mL Insulin Cartridges

  • Humalog – 28 days
  • Novolin R – 30 days
  • Novolin N – 7 days
  • Novolin 70/30 mix – 7 days

3 mL Insulin Cartridges

  • Novolin R – 28 days
  • Novolin N – 14 days
  • Novolin 70/30 mix – 10 days
  • NovoLog – 28 days

Prefilled Insulin Pens

  • Humalog – 28 days
  • Novolin R – 28 days
  • Novolin N – 14 days
  • Novolin 70/30 mix – 10 days
  • Novolog – 14 days