A sudden drop in a patient's blood pressure caused by standing or sitting upright is called postural hypertension. static hypotension. orthostatic hypotension. recumbent hypotension.

The correct term for a sudden drop in a patient's blood pressure caused by standing or sitting upright is **orthostatic hypotension**. Here's a brief explanation of the terms: - **Postural hypertension**: This term is not commonly used and may refer to an increase in blood pressure upon standing, which is not the case here. - **Static hypotension**: This term is not standard in medical terminology. - **Orthostatic hypotension**: This is the correct term, referring to a drop in blood pressure when a person stands up from a sitting or lying position. - **Recumbent hypotension**: This term refers to low blood pressure when lying down, which is not relevant to the situation described. Thus, the answer is **orthostatic hypotension**.