Insulin at Home: Pen Technique, Site Rotation, Storage, and Hypoglycemia
Teach rapid-acting insulin with meals and long-acting insulin once daily at the same time. For each pen injection, attach a new needle, prime 2 units, inject at 90 degrees, and hold for 10 seconds; rotate sites within one area. Never skip long-acting insulin during illness unless instructed, and treat glucose under 70 mg/dL with 15 g of fast-acting carbohydrate and a recheck in 15 minutes.
Who needs this teaching
Clients with type 1 or type 2 diabetes who use insulin at home, and the family member who helps. Insulin is a high-alert medication; errors in dosing, technique, or storage cause hypoglycemia or hyperglycemia.
The priority teaching points
- Insulin types. Rapid-acting insulin (lispro, aspart, glulisine) has an onset of about 15 minutes. Inject it within 15 minutes before a meal, or as prescribed, and eat after the injection. Long-acting insulin (glargine, degludec) provides a steady basal level without a pronounced peak. Inject it once daily at the same time. Never mix long-acting insulin with another insulin.
- Pen technique. Wash the hands. Check the insulin name, expiration date, and appearance; rapid-acting and long-acting insulins are clear. Attach a new needle. Prime 2 units with the needle pointing up until a drop appears. Dial the dose. Insert the needle at 90 degrees into clean, dry skin. Press the button fully and hold for 10 seconds, or the time in the pen instructions, before removing the needle. Remove and discard the needle after each injection.
- Site rotation. Use the abdomen (at least 2 inches from the umbilicus), the front and outer thigh, or the back of the upper arm. Rotate sites within one area, about 1 inch from the last injection. Repeated injection into one spot causes lipohypertrophy (fatty lumps) and erratic absorption. Avoid lumps, scars, and bruises.
- Storage. Store unopened insulin in the refrigerator at 36 to 46 F (2 to 8 C). Never freeze it. Keep the in-use pen at room temperature, below 86 F (30 C). Discard it after the number of days on the label. Never share a pen, even with a new needle; backflow of blood into the cartridge transmits bloodborne infections.
- Glucose monitoring. Check blood glucose before each meal and at bedtime, or on the prescribed schedule. Record each result with the insulin dose.
- Hypoglycemia. Glucose under 70 mg/dL is hypoglycemia: tremor, diaphoresis, tachycardia, hunger, anxiety, and confusion. Apply the rule of 15: take 15 g of fast-acting carbohydrate, recheck in 15 minutes, and repeat while glucose stays under 70 mg/dL, then eat a snack or meal. The family gives prescribed glucagon when the client cannot swallow safely, then calls 911.
- Sick days. Illness raises blood glucose. Never skip long-acting insulin during illness unless the provider instructs. Check glucose every 2 to 4 hours and follow the written sick-day plan.
- Sharps disposal. Place used needles in an FDA-cleared sharps container, or a heavy-duty plastic container with a tight lid, such as a laundry detergent bottle. Never put loose needles in the trash or recycling.
Red flags the client reports
| Call the provider the same day | Call 911 or the local emergency number |
|---|---|
| Repeated glucose readings under 70 mg/dL | Unconsciousness or seizure |
| Glucose over 300 mg/dL on 2 readings in a row | Inability to swallow safely: the family gives glucagon, then calls 911 |
| Vomiting or inability to eat during illness | Very high glucose with vomiting, deep rapid respirations, or fruity breath odor |
Teach-back questions
- "Show me how you prime your pen and give your dose."
- "When do you take your mealtime insulin in relation to your meal?"
- "Where will you inject next, and why do you rotate sites?"
- "How do you store your unopened and in-use pens?"
- "What will you do if your glucose is 58?"
Teaching tips
- Observe a full return demonstration with the client's own pen.
- Write each insulin name, dose, and time on the handout.
- Include a family member in glucagon teaching.
Read more on NCLEXPace
- Insulin: Types, Timing, and the Questions Built On Them
- High-Alert Medications: The Four That Hurt People Most
- Endocrine Map: DKA vs. HHS, Addison’s vs. Cushing’s, Thyroid Emergencies
Sources
- Harding MM, Kwong J, Hagler D, Reinisch C. Lewis's Medical-Surgical Nursing: Assessment and Management of Clinical Problems. 12th ed. Elsevier; 2023; Chapter: Diabetes.
- American Diabetes Association Professional Practice Committee. Standards of Care in Diabetes-2025. Diabetes Care. 2025;48(Suppl 1).
- Insulin Lispro Injection and Insulin Glargine Injection: FDA prescribing information and Instructions for Use (DailyMed).
Why this matters for the NCLEX
Teaching is effective when the client states, "I prime 2 units before every dose and hold the pen in place for 10 seconds," and "I take my long-acting insulin even when I am sick." Statements requiring further teaching include, "I inject in the same spot because it hurts less," "I keep my in-use pen in the glove compartment of my car," and "My husband and I share a pen, but we change the needle."
Frequently asked questions
Does the client skip long-acting insulin when unable to eat during illness?
No. Basal insulin needs continue during illness, and illness raises glucose. The client checks glucose more often and calls the provider for dose instructions.
Why does the client never share an insulin pen, even with a new needle?
Blood flows back into the cartridge during injection. Sharing transmits hepatitis B, hepatitis C, and HIV.
More patient teaching on Endocrine (Diabetes, Thyroid)
Hypoglycemia and Sick-Day Rules: The Rule of 15, Glucagon, and Ketone ChecksTeach recognition and treatment of hypoglycemia with the rule of 15, glucagon use by family members, prevention, and sick-day management of insulin, glucose checks, fluids, and ketones.Type 2 Diabetes: Glucose Targets, Metformin Safety, and Daily Foot CareTeach blood glucose monitoring and targets, the plate method, physical activity, metformin safety, daily foot care, yearly screening, and recognition of hyperglycemic emergencies.Hyperthyroidism: Antithyroid Medication Safety, Radioactive Iodine Precautions, and Thyroid StormTeach antithyroid medication safety, beta blocker use, radioactive iodine precautions, Graves eye care, nutrition, and recognition of thyroid storm.3,200+ NCLEX questions with think-like-a-nurse rationales, unfolding case studies and adaptive readiness exams. Start with free practice questions, then choose a plan when you are ready.
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