Insulin Pen Technique and Hypoglycemia in a Newly Discharged Patient
A 58-year-old man with type 2 diabetes is discharged after a 4-day admission for cellulitis. His discharge prescription is insulin glargine 20 units subcutaneously at bedtime, plus metformin 1,000 mg BID. Before admission he took only metformin. He lives alone, works night shifts as a security guard, and has never used insulin. He tells you he is nervous about "giving himself shots" and asks whether he can take the insulin only on days he feels his sugar is high. His discharge glucose log shows fasting readings of 9-11 mmol/L and one reading of 3.6 mmol/L on the morning of discharge after a missed dinner. The pharmacy has his pen and needles in stock.
1. How do you address his question about taking insulin only when glucose is high?
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Answer: Explain that insulin glargine is a long-acting basal insulin that works continuously over roughly 24 hours; it is not a "rescue" medication to be taken only when glucose is high. Skipping doses causes glucose to drift upward and increases risk of hyperglycemia and, in the context of recent infection, readmission.
Tailor to his life:
- He works nights, so "bedtime" should mean the time he goes to sleep, not a fixed clock time. Consistency matters more than the exact hour.
- The 3.6 mmol/L reading after a missed meal is a warning: basal insulin can cause hypoglycemia if meals are skipped, especially with night-shift eating patterns.
- Discuss a consistent meal pattern, checking glucose before driving and during shifts, and keeping fast-acting carbohydrate nearby.
Do not simply say "take it every day" without addressing the hypoglycemia risk and his work schedule. If adherence is a concern, involve the prescriber about regimen simplification.
2. Demonstrate the key teaching points for insulin pen use and hypoglycemia recognition.
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Pen technique:
- Wash hands; check the pen label and insulin type, and check the expiry date.
- Attach a new needle; prime with 2 units and confirm a drop appears.
- Dial the prescribed 20 units; confirm the dose window.
- Inject into the abdomen, thigh, or upper arm, rotating sites; hold the needle in for about 10 seconds after injecting.
- Remove the needle and dispose of it in a sharps container; never share pens.
- Store unopened pens in the fridge; in-use pens at room temperature, away from heat and light.
Hypoglycemia: Teach the 15-15 rule - 15 g fast-acting carbohydrate (e.g., 4 oz juice or glucose tablets), recheck in 15 minutes, repeat if still low. Recognize symptoms: shakiness, sweating, confusion, hunger, palpitations. Because he lives alone and works nights, advise keeping glucose tablets at work and in the car, and tell a coworker about his insulin use.
Confirm: Use teach-back - have him demonstrate dialing and injecting on a trainer pen and explain what he would do for a low reading.
3. What follow-up and interprofessional communication would you arrange?
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Follow-up:
- Phone follow-up in 3-7 days to review glucose readings, injection technique, and any lows.
- Recommend a glucose log with fasting and pre-meal readings, especially around night shifts.
- Discuss the 3.6 mmol/L episode with the prescriber - it may warrant dose adjustment or review of meal timing.
- Confirm he has a sharps container and enough needles and test strips.
Interprofessional communication:
- Send a note to the prescriber or diabetes educator summarizing the teaching provided, his concerns, and the hypoglycemia episode.
- Refer to a diabetes education program if available, given his new insulin start and shift work.
- If he has a community nurse or pharmacist-led monitoring program, coordinate a follow-up visit.
Documentation: Record the teaching, teach-back result, the hypoglycemia history, and the referrals made.