Which term describes reduced urine production?

• A. Polyuria
• B. Nocturia
• C. Oliguria
• D. Uremia

Answer: (C)

Oliguria describes reduced urine production. It refers to urine output that is lower than normal, often defined in adults as less than about 400 mL in a 24-hour period, or less than 0.5 mL/kg/hour. This can occur with dehydration, kidney injury, obstruction, or reduced blood flow to the kidneys, and it signals that the kidneys are not producing urine as usual.

In contrast, polyuria means excessive urine production, which is the opposite of oliguria. Nocturia is specifically urinating during the night, which can accompany polyuria but focuses on the timing rather than the overall amount. Uremia is a condition where waste products build up in the blood due to kidney failure, a systemic issue related to kidney function rather than just the level of urine output.