Pharmacology · Topic 81 of 102
Insulin Administration Technique
Drawing up two insulins in the wrong order can destroy an entire vial — and the wrong injection technique can turn rapid-acting insulin into something dangerously unpredictable.
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Insulin Administration Technique
A high-alert drug: unit syringe, clear before cloudy, food timing. Long-acting is never mixed.
Two insulin vials stand side by side: REGULAR, which is clear, and NPH, which is cloudy, with a unit-marked insulin syringe. It draws up the clear regular insulin first, then moves to the NPH vial and draws the cloudy NPH in after it: clear before cloudy.
- Draw the clear regular firstNurse seesregular looks clear — a cloudy regular vial is not usedNurse doesunit-marked insulin syringe
- Then the cloudy NPH: clear before cloudyNurse seesNPH evenly cloudy after rolling — never shakenNurse doesa second nurse verifies the dose
Regular (clear) is drawn up before NPH (cloudy) · never mix glargine, detemir or degludec with any insulin
e.g. a DKA drip · NPH, glargine and degludec are never given IV · monitor K⁺ on IV insulin
Never an mL syringe · high-alert: a second nurse verifies the dose
Timing with food
Before you injectRapid-acting goes in only with the meal tray there
Giving the injection
SubQ techniqueInto the fat: 90° if there's enough fat, 45° if the patient is thin
Roll gently between the palms (and invert) until evenly cloudy.
Keeps absorption consistent and prevents fatty lumps (lipohypertrophy). Never inject into lumpy or thickened skin.
Moving from a lumpy site to healthy tissue can suddenly raise absorption — watch the glucoseKeep the button pressed about 10 seconds (per the pen's instructions — some say 5). Never share a pen, even with a new needle.
More detail
Red flags
Stop · checkIf the glucose drops
Rule of 1515 g fast carbs · recheck in 15 minutes · repeat if still low · then a snack
Nursing priorities
In orderClear or cloudy?
Know the vials| Looks | Clear — cloudy = don't use |
|---|---|
| Mix? | Yes — drawn up first |
| IV? | Yes — the IV insulin |
Teach your patient
Storage + safetyClear before cloudy — and long-acting stands alone. Regular is the one that goes IV.
Sources · Humulin R U-100 label · Humulin N label · Humalog label · Lantus label · Tresiba label · OpenStax Clinical Nursing Skills 12.3 · OpenStax Clinical Nursing Skills 12.5 · Open RN Nursing Skills, Ch. 18 · CDC: Treatment of Low Blood Sugar · Films: the NurseSavvy learning-flow visuals. Follow your facility's protocol.
Insulin Administration Technique
Drawing up two insulins in the wrong order can destroy an entire vial — and the wrong injection technique can turn rapid-acting insulin into something dangerously unpredictable.
Insulin is administered subcutaneously at a 90-degree angle (or 45 degrees for thin patients) into rotating sites: abdomen (fastest absorption), arms, thighs, and buttocks (slowest). Site rotation within the same anatomic region prevents lipodystrophy while maintaining predictable absorption. When mixing insulins in one syringe, always draw up clear (regular) before cloudy (NPH) — "clear before cloudy." This protects the regular insulin vial from contamination with NPH, which would alter its onset. Roll NPH gently between palms to resuspend — never shake, as this denatures the protein and creates air bubbles. Opened insulin vials are stable at room temperature for 28 days; refrigerated until first use. Inject at room temperature to reduce pain and ensure consistent absorption. After injection, do not massage the site — this accelerates absorption unpredictably. For pen devices, hold the needle in the skin for 10 seconds after injection to ensure full dose delivery. Only regular insulin may be given IV; all other formulations are subcutaneous only.
Key Distinctions
Don't confuse injection site rotation (moving within the same region, e.g., different spots on the abdomen) with switching regions entirely each dose — same-region rotation maintains consistent absorption. Students mix up the mixing rule: clear (regular) is drawn first into the syringe, then cloudy (NPH) is drawn second. Never mix long-acting analogs (glargine, detemir) with any other insulin — they cannot be combined in the same syringe.
Clinical Pearl
Clear before cloudy, roll don't shake, abdomen absorbs fastest. If you contaminate the regular vial with NPH, that vial is ruined.
Knowledge Check
3 quick questions on the must-knows for this topic.
When mixing insulins, which is drawn up first?
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