Which term corresponds to a sustained drop in blood pressure upon standing?

• A. Hypertension
• B. Acidosis
• C. Hypotension
• D. Orthostatic hypotension

Answer: (D)

When you stand, the body must quickly adjust blood pressure to keep blood flow to the brain. If this adjustment fails and the blood pressure remains low after standing, it is called orthostatic hypotension. This occurs because blood pools in the legs and the reflexes that raise vascular tone or heart rate don’t compensate enough, leading to a sustained drop in blood pressure after standing.

This is distinct from hypertension, which means high blood pressure, and from hypotension in general, which refers to low blood pressure regardless of posture. Acidosis is a different issue altogether—an acid–base disorder with low pH that doesn’t describe posture-related BP changes. Orthostatic hypotension often presents with dizziness or faintness upon standing and can result from dehydration, certain medications, or autonomic dysfunction.