What is the management protocol for diabetes using an insulin pen (Insulin Delivery Device)?

Management Protocol for Insulin Pen Use in Diabetes

For patients with insulin-requiring diabetes on multiple daily injections, insulin pens are the preferred delivery method over syringes in most cases, offering superior convenience, accuracy, and patient satisfaction. 1

Device Selection and Patient Assessment

Insulin pens should be the first-line choice when selecting insulin delivery devices, with syringes reserved only when specific circumstances dictate otherwise 1. The 2024 American Diabetes Association guidelines explicitly state this preference, representing the most current evidence-based recommendation 1.

When to Choose Insulin Pens:

• Patients with dexterity issues or vision impairment - insulin pens or injection aids are specifically recommended to facilitate accurate dosing 1
• Patients preferring simplicity and convenience - trials demonstrate equivalence or small improvements in glycemic outcomes compared to vial/syringe, with higher patient preference 1
• Most ambulatory diabetes patients - pens are now standard in mainstream care 2

When Syringes May Be Considered:

• Cost constraints - significant price differences may exist between pen and vial formulations 1
• Insulin type availability - some insulins are only available in vials 1
• Patient/caregiver preference after shared decision-making 1
• Resource-limited settings - syringes may be reused by the same individual with appropriate storage and cleansing, though this is not manufacturer-recommended 1, 3

Pen Types and Features

Available Pen Options:

• Disposable pens with prefilled cartridges 1
• Reusable pens with replaceable insulin cartridges, some with memory functions for dose amounts and timing 1
• Connected/smart pens - can be helpful for diabetes management, providing dose capture, dosing recommendations, and downloadable data reports 1

Dosing Capabilities:

• Dose range: 1 to 80 units per injection in most pens 4
• Dose increments: vary from 0.5-unit to 2-unit increments depending on pen model 1
• Total capacity: typically 300 units per pen device 4

Proper Injection Technique Protocol

Pre-Injection Steps:

Step 1: Pen Preparation 4

• Remove pen from refrigerator at least 1 hour before injection (cold insulin causes more pain)
• Check insulin name and expiration date on label
• Verify insulin is clear (do not use if cloudy, colored, or contains particles)
• Wipe rubber seal with alcohol swab

Step 2: Needle Attachment 4

• Always use a new sterile needle for each injection to prevent blocked needles, contamination, and infection
• Use 4-mm pen needles as first-line choice - shortest needles are safe, effective, less painful, and reduce risk of intramuscular injection 3
• Needle gauge ranges from 22-34 (higher number = thinner needle, less pain) 1
• Screw needle straight onto pen until fixed; do not overtighten

Step 3: Safety Test 4

• Select 2 units and press injection button fully
• Insulin should appear at needle tip (repeat up to 3 times if needed)
• If no insulin appears after third attempt, change needle and repeat; if still unsuccessful, use new pen
• Air bubbles are normal and will not cause harm

Injection Site Selection and Rotation:

Approved injection sites 4:

• Upper legs (thighs)
• Upper arms
• Stomach area (abdomen)

Critical site rotation protocol 4:

• Rotate injection sites within chosen area for each dose to reduce risk of lipodystrophy (pits/thickened skin) and localized cutaneous amyloidosis (lumps)
• Never inject where skin has pits, is thickened, has lumps, is tender, bruised, scaly, hard, scarred, or damaged
• Annual examination of injection/infusion sites is required, and more frequently if clinical issues arise 1

Injection Execution:

Step-by-step injection 4:

1. Select prescribed dose using dose selector
2. Insert needle into skin as demonstrated by healthcare provider
3. Press injection button fully and hold
4. Count slowly to 10 after dose window shows "0" to ensure full dose delivery
5. Release button and remove needle from skin

Post-Injection Steps:

Needle removal and disposal 4:

• Guide needle straight into outer needle cap (avoid angling to prevent puncture)
• Unscrew and dispose of needle in puncture-resistant container
• Never store pen with needle attached
• Replace pen cap

Storage Requirements

Before First Use: 4

• Refrigerate at 36°F to 46°F (2°C to 8°C)
• Never freeze - do not use if insulin has been frozen

After First Use: 4

• Store at room temperature below 86°F (30°C)
• Keep away from heat and light
• Do not refrigerate after first use
• Discard after 28 days, even if insulin remains

Insulin Regimen Selection

Type 1 Diabetes:

Multiple daily injections required from diagnosis, consisting of 1, 3:

• Rapid-acting or short-acting insulin 0-15 minutes before meals
• One or more daily injections of intermediate or long-acting basal insulin
• Alternative: 2-3 premixed insulin injections daily

Type 2 Diabetes:

Initial therapy - Basal insulin only 3, 2:

• Start with long-acting basal insulin (insulin glargine 100 U/mL preferred, originator or biosimilar) 2
• Begin with fixed dose (e.g., 10 units/day) 2
• Titrate by 2 units twice weekly based on fasting glucose, targeting <5.5 mmol/L (<100 mg/dL) 5, 2
• Continue metformin and GLP-1 receptor agonists 3, 6

Intensification when needed 3, 2:

• Add meal-time rapid-acting insulin analogue when basal insulin optimized but targets not met
• Use fasting plasma glucose to titrate basal insulin; use both fasting and postprandial glucose to titrate meal-time insulin 3

Dose Calculation Support

FDA-approved bolus calculators should be used when patients desire automated dosing assistance 1:

• Only use FDA-approved systems to ensure safety and efficacy of algorithms 1
• Healthcare professional input essential for initial dosing calculations with ongoing follow-up for adjustments 1
• Connected insulin pens can provide dose capture and recommendations 1

Important regulatory note: In the UK and EU, some insulin dose calculator apps (like Glooko) lack regulatory approval for dose calculation functionality, requiring manual calculations by healthcare providers 7

Common Pitfalls and Caveats

Critical Safety Issues:

• Intramuscular injections must be avoided, especially with long-acting insulins, as severe hypoglycemia may result 3
• Lipohypertrophy is frequent and distorts insulin absorption - never inject into these lesions 3
• Needle reuse is associated with lipohypertrophy development and should be avoided 3
• Do not use syringe to remove insulin from pen - this can cause dosing errors 4

Device Handling:

• Handle pen with care; do not drop or knock against hard surfaces 4
• If pen appears damaged, do not attempt repair - use new pen 4
• Clean only with damp cloth (water only); do not soak, wash, or lubricate 4

Medication Continuity:

• Do not abruptly discontinue oral medications when starting insulin due to rebound hyperglycemia risk 3
• Metformin combined with insulin reduces weight gain, lowers insulin dose requirements, and decreases hypoglycemia compared to insulin alone 3