**Question:** GLP-1 analogue used in diabetes mellitus -

A. Exenatide (Byetta)
B. Liraglutide (Victoza)
C. Albiglutide (Tanzeum)
D. Dulaglutide (Trulicity)

**Correct Answer: D. Dulaglutide (Trulicity)**

**Core Concept:** Glucagon-like peptide-1 (GLP-1) analogues are a class of medications used in the treatment of type 2 diabetes mellitus. They work by mimicking the actions of natural GLP-1, a hormone released by the enteroendocrine L cells in the gastrointestinal tract in response to food intake.

**Why the Correct Answer is Right:** Dulaglutide (Trulicity) is a GLP-1 receptor agonist, meaning it stimulates the GLP-1 receptor, leading to improved glucose control. It has a longer half-life compared to other GLP-1 analogues, allowing for once-weekly administration. This dosing regimen provides greater convenience and better adherence for patients, making it a preferred choice over other available GLP-1 analogues.

**Why Each Wrong Option is Incorrect:**

A. Exenatide (Byetta) is also a GLP-1 analogue but has a shorter half-life and requires twice-daily administration.
B. Liraglutide (Victoza) has a similar half-life to dulaglutide but is administered once daily, not once weekly.
C. Albiglutide (Tanzeum) is another GLP-1 analogue but has a shorter half-life and requires once-weekly administration, similar to dulaglutide.

**Clinical Pearl:** GLP-1 analogues are part of a broader class of medications called incretin-based therapies, which also includes dipeptidyl peptidase-4 (DPP-4) inhibitors like sitagliptin (Januvia). These medications work together with the pancreas to improve glucose control in patients with type 2 diabetes mellitus.

**Core Concept:** Incretin-based therapies use a combination of incretin hormones, like GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), to stimulate insulin secretion and suppress glucagon release in response to meals, thereby regulating blood glucose levels.

**Why Each Wrong Option is Incorrect:**

A. Exenatide (Byetta) and liraglutide (Victoza) are administered via subcutaneous injections, while dulaglutide (Trulia) is administered via subcutaneous injections as well, making option C incorrect.
B. Dulaglutide (Trulia) has a longer half-life than exenatide (Byetta), making option C incorrect.
C. Albiglutide (Tanzeum) and lixisenatide (Letfam) are administered via subcutaneous injections, while dulaglutide (Trulia) is