Diabetes Insulin Therapy 3 — Questions and Answers
Question 1: Which insulin formulation has the longest duration of action?
- Regular insulin
- NPH insulin
- Insulin degludec (Tresiba) (Correct answer)
- Insulin aspart (NovoLog)
Correct answer: Insulin degludec (Tresiba)
Degludec (Tresiba) has an ultra-long duration exceeding 42 hours, providing very stable basal coverage with minimal peak.
Question 2: A patient's fasting blood glucose is consistently elevated despite adequate evening basal insulin. The most likely explanation is:
- Insufficient mealtime bolus at dinner
- The Somogyi effect — nocturnal hypoglycemia followed by rebound (Correct answer)
- Basal insulin dose is too high
- The patient is skipping breakfast
Correct answer: The Somogyi effect — nocturnal hypoglycemia followed by rebound
The Somogyi effect (rebound hyperglycemia) occurs when nocturnal hypoglycemia triggers counter-regulatory hormone release, raising morning glucose.
Question 3: When mixing NPH and regular insulin in one syringe, which should be drawn up first?
- NPH (cloudy) first
- Regular (clear) first (Correct answer)
- Either order is acceptable
- They should never be mixed
Correct answer: Regular (clear) first
Clear before cloudy — regular insulin is drawn first to prevent contaminating the clear vial with NPH, which would alter its action profile.
Question 4: What is the primary advantage of using an insulin-to-carbohydrate ratio (ICR)?
- It eliminates the need for blood glucose monitoring
- It allows individualized mealtime dosing based on carbohydrate intake (Correct answer)
- It reduces the number of daily injections required
- It prevents all episodes of postprandial hypoglycemia
Correct answer: It allows individualized mealtime dosing based on carbohydrate intake
The ICR enables patients to calculate precise mealtime bolus doses based on the actual carbohydrates they plan to consume.
Question 5: A patient using glargine (Lantus) reports a painful burning sensation at injection. The most likely cause is:
- Expired insulin
- Injecting too rapidly or insufficient subcutaneous depth (Correct answer)
- Allergic reaction requiring epinephrine
- Incorrect mixing with another insulin
Correct answer: Injecting too rapidly or insufficient subcutaneous depth
Glargine has an acidic pH that can cause a burning sensation, especially when injected too quickly or superficially.
Question 6: Which factor most significantly increases insulin absorption rate?
- Injecting into the thigh
- Injecting into the abdomen
- Exercising the injected limb immediately after injection (Correct answer)
- Using a shorter needle
Correct answer: Exercising the injected limb immediately after injection
Exercise increases blood flow to the injected muscle, dramatically accelerating subcutaneous insulin absorption and raising hypoglycemia risk.
Question 7: For a patient with Type 2 diabetes starting basal insulin, the typical starting dose is:
- 0.5–1.0 units/kg/day
- 10 units once daily or 0.1–0.2 units/kg/day (Correct answer)
- 20 units twice daily
- Based solely on HbA1c level
Correct answer: 10 units once daily or 0.1–0.2 units/kg/day
ADA guidelines recommend starting basal insulin at 10 units/day or 0.1–0.2 units/kg/day, then titrating based on fasting glucose.
Diabetes Insulin Therapy 3
Which insulin formulation has the longest duration of action?