**Question:** True about lispro–insulin is: a) Action is faster and short in duration than regular insulin; b) It is given 15 minutes prior to meal; c) Source is lamb; d) Action is faster and of longer duration than regular insulin.

**Core Concept:** Lispro insulin is a rapid-acting insulin analogue developed to provide faster onset and shorter duration of action compared to regular insulin. It is designed to mimic the action of human insulin and is commonly used in the treatment of type 1 and type 2 diabetes.

**Why the Correct Answer is Right:**

Correct Answer: Lispro insulin (D) has a faster onset and longer duration of action than regular insulin. This is due to its molecular structure, which is similar to human insulin but contains a few modifications, making it more potent and stable. These changes result in a faster absorption and action compared to regular insulin.

**Why Each Wrong Option is Incorrect:**

A. Action is faster and short in duration than regular insulin (incorrect) - This statement is incorrect because lispro insulin has a faster onset but is not shorter in duration than regular insulin.

B. It is given 15 minutes prior to meal (incorrect) - Although lispro insulin has a faster onset, the timing of administration is not specified in the question, so we cannot confirm that it should be given 15 minutes before meals.

C. Source is lamb (incorrect) - Lispro insulin is not derived from lamb insulin but is a human insulin analogue. It is produced through genetic engineering techniques, making it a human insulin analogue.

**Clinical Pearl:**

Lispro insulin is a valuable tool in diabetes management, offering a more rapid and longer-lasting effect compared to regular insulin. Its faster onset allows for better control of blood glucose levels, especially during meals, while its longer duration helps maintain glucose levels throughout the day. However, the timing of administration and its source are incorrect in the question.

To ensure effective use of lispro insulin, it is usually administered 15-30 minutes prior to meals. Additionally, it is a human insulin analogue, not derived from lamb insulin.