Which of the following medications can cause dizziness?

The correct answer is HCTZ, which stands for hydrochlorothiazide. Hydrochlorothiazide is a thiazide diuretic commonly prescribed to treat hypertension and edema. One of the notable side effects of this medication is dizziness. This can occur due to its action in reducing blood volume and causing changes in blood pressure, particularly when a person stands up quickly, a condition known as orthostatic hypotension. Patients may experience lightheadedness or dizziness, especially when they first start taking the medication or when the dose is increased.

In contrast, while Ferrous Sulfate (an iron supplement), Flonase (a nasal spray for allergies), and Folvite (a form of folic acid) can have side effects, they are less commonly associated with dizziness. Ferrous Sulfate may cause gastrointestinal discomfort, Flonase primarily works on nasal congestion and does not typically induce dizziness, and Folvite is essential for cellular function without direct effects on blood pressure or similar pathways that could lead to dizziness. Therefore, HCTZ stands out as the medication most likely to cause dizziness among the options provided.