Insulin – zinc suspension or Lente insulin is ?
**Core Concept:** Insulin is a hormone produced by the beta cells of the pancreas that regulates blood glucose levels by facilitating glucose uptake into cells. Insulin is available in different forms based on its rate of absorption and duration of action.
**Why the Correct Answer is Right:** Insulin-zinc suspension (also known as RAPID-acting insulin) is a fast-acting insulin that mimics the postprandial insulin release and has a short duration of action (4-6 hours). When insulin is mixed with zinc, it retains its bioactivity and slows down its release, allowing for a more sustained effect. Zinc also protects insulin from degradation.
**Why Each Wrong Option is Incorrect:**
A. **Lente insulin (also known as Regular insulin):** This is a long-acting insulin that provides basal insulin secretion and has a duration of action of 16-24 hours. Lente insulin is not mixed with zinc, which is why it has a longer duration of action.
B. **Aspart insulin (also known as NovoRapid):** Aspart insulin is a rapid-acting insulin analogue with a duration of action of 4-6 hours. It is not mixed with zinc and therefore does not have the same sustained effect as insulin-zinc suspension.
C. **Glargine insulin (also known as Lantus):** Glargine insulin is a long-acting insulin analogue with a duration of action of 24 hours. It is not mixed with zinc and does not have the same sustained effect as insulin-zinc suspension.
D. **Insulin-zinc suspension (also known as Insulin aspart or insulin glulisine):** This is the correct answer as it describes a type of insulin that is mixed with zinc for a sustained effect, making it suitable for basal insulin administration in type 1 diabetes.
**Clinical Pearl:** The use of insulin-zinc suspension enables patients with type 1 diabetes to have a more consistent blood glucose control throughout the day and night, while avoiding the peaks and troughs associated with rapid-acting insulin alone.
Insulin-zinc suspension is commonly used for basal insulin administration in type 1 diabetes to mimic the physiological insulin release pattern.