Some insulin pens are designed to be used with an insulin cartridge. These pens are meant to be reused. Insulin pens that do not come with separate insulin cartridges are disposable, and the insulin is prefilled inside the pen. When you prepare to take
insulin, check the label on the bottle (vial), the disposable pen, or the cartridge for the refillable pen for the:
Expiration date of the
Correct name and source of insulin (human or pig)
prescribed for you.
Correct type of insulin prescribed for you
(rapid-, short-, intermediate-, or long-acting, or mixed).
concentration of insulin prescribed for you. (The most commonly used
concentration is U-100, which contains 100 units of insulin per milliliter or
cubic centimeter.) Sometimes insulin is produced in a less concentrated
(diluted) form for babies. Make sure you give your baby the dilution your
Also, check the bottle, pen, or cartridge for cracks or chips. Look for
changes in the appearance of the insulin that can indicate it will not work,
A coating of white crystals on the inside surface
of the bottle.
A grainy look or clumping or curdling of the
Other changes in the insulin's clarity or color.
ByHealthwise Staff Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine Specialist Medical ReviewerDavid C.W. Lau, MD, PhD, FRCPC - Endocrinology