Question 1
A 58-year-old man with type 2 diabetes is starting insulin glargine 100 units/mL (Lantus SoloStar) pens. He travels for work and may not always have access to a refrigerator once a pen is in use. He asks how long an opened pen can be kept at room temperature and when it must be discarded. He also wonders if the expiration date on the box still applies after starting the pen. Provide guidance on storage and in-use stability for this basal insulin.
Which of the following represents the correct storage or stability condition for this drug?
- After first use, pens are stable at room temperature for 28 days; discard after 28 days.
- Pens must remain refrigerated during use; discard 56 days after first use.
- Once opened, store at room temperature and discard after 42 days.
- Once opened, keep frozen between uses to prevent degradation.
Explanation: Lantus SoloStar pens in use are stable at room temperature for 28 days and should be discarded after that time. Requirements to refrigerate during use or longer 42- or 56-day in-use periods, as well as freezing, are incorrect.