What education should be provided to a patient for home insulin administration?

Patient Education for Home Insulin Administration

Patients starting home insulin therapy must receive comprehensive, structured education on proper storage, injection technique, and site rotation to prevent complications like lipodystrophy and ensure optimal glycemic control. 1

Insulin Storage and Handling

Unopened Insulin

• Store in refrigerator at 2-8°C (36-46°F) without freezing
• Check your home refrigerator temperature, as many household units fall outside this range
• Use cooler packs or insulated bags when transporting insulin in hot or cold weather 1

Opened Insulin (In Use)

• Store at room temperature 15-30°C (59-86°F) away from direct sunlight
• Discard after manufacturer's expiration date (typically 28 days)
• Never store insulin immersed in water - this causes contamination and loss of potency 2

Before Each Injection

• Verify the insulin label to avoid using the wrong type 3
• Check that insulin is not expired or inappropriately cloudy
• For cloudy insulins (like NPH): gently roll/tip the vial or pen until crystals dissolve - do not shake vigorously as this creates air bubbles 1
• Allow refrigerated insulin to reach room temperature (30-60 minutes) before injecting - cold insulin causes pain and contributes to lipodystrophy 1

Injection Site Selection and Rotation

Recommended Sites

Preferred sites with adequate subcutaneous fat include:

• Abdomen (preferred)
• Thighs
• Buttocks
• Upper arms (least preferred for self-injection due to difficulty maintaining 90° angle) 1

Sites to AVOID

• Areas with lipodystrophy (lumps, bumps, or thickened skin)
• Scars, stretch marks, or tattoos
• Areas showing edema, infection, inflammation, or ulceration
• Never inject through clothing 1

Systematic Rotation Strategy

This is critical to prevent lipodystrophy:

• Divide each body zone into quadrants or halves
• Use one zone quadrant/half per week
• Within each zone, inject at least 1 cm apart (approximately one adult finger width) from previous injections
• Rotate in a consistent direction
• If giving two injections simultaneously (e.g., basal and prandial), use separate sites 1

Common pitfall: Patients often repeatedly inject into lipodystrophy areas because they're painless, but this worsens glycemic control and increases insulin requirements 4

Injection Technique for Insulin Pens

Device Preparation

1. Remove BOTH needle covers - the outer AND inner cover
   • Critical error: Failing to remove the inner needle cover prevents insulin delivery and can cause hyperglycemia or diabetic ketoacidosis 1
2. Prime the needle per manufacturer instructions until you see at least one drop of insulin at the needle tip
3. Verify sufficient insulin volume in pen
4. Dial the correct dose

Needle Selection

• Use 4-mm needle length (or 5-mm if 4-mm unavailable) for most adults
• Use 32-gauge or thinner diameter
• These specifications minimize pain and reduce intramuscular injection risk 1

Injection Procedure

1. Clean injection site with alcohol swab and let it air dry completely 1
2. Hold pen perpendicular to skin (90° angle) for most adults using 4-mm needles
3. Insert needle fully into skin
4. Press injection button completely with steady, even pressure using your thumb
5. Inject slowly
6. Wait 10 seconds after dose delivery before removing needle (reduces insulin leakage) 1
7. Watch for successful injection cues: dose dial returns to zero, no insulin droplets at needle tip, no wetness or bump at injection site

Injection Technique for Syringes

While pens are generally safer and more convenient, syringes remain viable and more affordable 1:

Dose Preparation

1. Verify insulin label
2. For cloudy insulins: gently roll vial in palms
3. Draw air equal to insulin dose and inject into vial first (prevents vacuum)
4. When mixing insulins: draw clear (rapid/short-acting) insulin first, then cloudy insulin 3
5. Flick syringe to remove air bubbles

Injection Procedure

• Most individuals can lightly grasp a skin fold, release the pinch, then inject at 90°
• Thin individuals or children may need 45° angle to avoid intramuscular injection
• Embed needle in skin for 5 seconds after complete delivery 3

Needle and Syringe Reuse

Reuse is NOT recommended 2. However, recognizing that many patients reuse due to cost:

If Reusing (Not Ideal)

• Discard when injections become more painful
• Never reuse more than 5 times 2
• Discard if needle is noticeably dull, deformed, or contacted any surface other than skin
• Must be able to safely recap (requires adequate vision, dexterity, no tremor)
• Patients with open wounds, decreased resistance to infection, or poor hygiene should NEVER reuse 3

Important: Even single-use of small-gauge needles can cause the tip to bend into a hook, potentially lacerating tissue 3

Follow-Up and Reassessment

• Healthcare providers should review injection technique and rotation practices at least annually 1
• Inspect injection sites regularly for lipodystrophy, which significantly increases hypoglycemia risk, glycemic variability, and insulin costs 4
• Video-based education has been shown to effectively improve patient knowledge and attitudes toward insulin therapy 5