What is Regular insulin used for?
- Type 1 and type 2 diabetes
- Diabetic ketoacidosis and hyperglycemic hyperosmolar state (IV infusion)
- Hyperkalemia (IV, given with dextrose)
Short-acting human insulin. Clear solution. U-100 is standard; Humulin R U-500 is five times more concentrated and is used only with its own dedicated pen or U-500 syringe.
How Regular insulin works
Replaces or supplements the body's insulin: moves glucose into cells, lowers blood glucose and pulls potassium into cells.
Common side effects
- Hypoglycemia
- Hypokalemia, especially with IV use
- Weight gain
- Injection-site reactions and lipodystrophy
Report right away
- Shakiness, sweating, fast heartbeat, confusion or hunger (low blood sugar)
- Blood glucose that stays above the target your provider set
Nursing considerations for Regular insulin
- Onset about 30 to 60 minutes, peak about 2 to 4 hours, duration about 5 to 8 hours when given subcutaneously.
- Regular insulin is the insulin used for continuous IV infusions; monitor glucose (often hourly) and potassium during an infusion.
- High-alert medication: independent double check, an insulin syringe for U-100 vials, and the correct concentration.
- When mixing with NPH, draw up regular (clear) before NPH (cloudy).
Patient teaching
- Inject about 30 minutes before a meal.
- Carry fast-acting sugar (glucose tablets, juice) and know the signs of low blood sugar.
- Rotate injection sites within the same body area.
This card does not list doses. Use the prescriber's order, the product label and a current drug reference for dosing, and follow your facility's policies.
Insulins practice questions
NCLEX-style questions on the class Regular insulin belongs to.
3 questions. Choose an answer to see the rationale.
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When mixing regular and NPH insulin in one syringe, which insulin is drawn up first?
Show answer
Answer A: Regular (clear) Clear before cloudy: draw up regular first so that NPH (which contains protamine) does not contaminate the regular insulin vial.
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A patient received NPH insulin at 0700. At what time is hypoglycemia most likely?
Show answer
Answer A: Early to mid-afternoon NPH peaks about 4 to 12 hours after injection, so a morning dose peaks in the afternoon.
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Which insulin can be given by continuous IV infusion?
Show answer
Answer D: Regular Regular insulin is the insulin routinely used for IV infusions. Glargine, NPH and premixed insulins are subcutaneous only.
Frequently asked questions
What is Regular insulin used for?
Type 1 and type 2 diabetes; Diabetic ketoacidosis and hyperglycemic hyperosmolar state (IV infusion); Hyperkalemia (IV, given with dextrose).
What drug class is Regular insulin?
Regular insulin belongs to the class insulins. Replaces or supplements the body's insulin: moves glucose into cells, lowers blood glucose and pulls potassium into cells.
What are the nursing considerations for Regular insulin?
Onset about 30 to 60 minutes, peak about 2 to 4 hours, duration about 5 to 8 hours when given subcutaneously. Regular insulin is the insulin used for continuous IV infusions; monitor glucose (often hourly) and potassium during an infusion.
What should patients report while taking Regular insulin?
shakiness, sweating, fast heartbeat, confusion or hunger (low blood sugar); blood glucose that stays above the target your provider set.