## **Core Concept**
Dapagliflozin is a **sodium-glucose cotransporter 2 (SGLT2) inhibitor**, a class of medications used in the treatment of **type 2 diabetes mellitus**. SGLT2 inhibitors work by blocking the reabsorption of glucose in the kidneys, leading to increased urinary glucose excretion. This mechanism can also lead to various side effects due to the increased glucose levels in the urine.

## **Why the Correct Answer is Right**
The most common side effect of dapagliflozin is **genital mycotic infections**, particularly **vulvovaginal candidiasis** in women and **balanitis** in men. This is because the increased glucose in the urine provides a favorable environment for the growth of yeast. The mechanism of action of dapagliflozin directly contributes to this side effect, making it a well-recognized and common adverse effect of this class of drugs.

## **Why Each Wrong Option is Incorrect**
- **Option A:** While dapagliflozin can cause **hypoglycemia**, it is not the most common side effect, especially when used as monotherapy. Hypoglycemia is more commonly associated with other classes of diabetes medications like insulin secretagogues or insulin.
- **Option B:** **Polyuria** can occur due to the osmotic effect of glucose in the urine, but it is not as frequently emphasized as a side effect compared to genital mycotic infections.
- **Option C:** This option is not provided, but typically, other potential side effects like **dehydration** or **urinary tract infections** can occur but are not the most common.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl for SGLT2 inhibitors like dapagliflozin is that patients should be counseled about the increased risk of **genital infections** and advised on proper hygiene and the potential need for antifungal treatments. This is a high-yield fact because it directly impacts patient care and management.

## **Correct Answer:** D. Genital mycotic infections.