Which sign most strongly suggests dehydration in an older adult?

• A. Dark yellow urine.
• B. Thirst (when present).
• C. Dry mucous membranes and skin.
• D. Dizziness.

Answer: (C)

In older adults, the strongest sign of dehydration is dry mucous membranes and dry skin. These signs reflect a real fluid deficit in the body and are more directly tied to dehydration than other indicators. Thirst may be absent or blunted in many older people, making it an unreliable cue. Dark yellow urine can hint at concentrated urine, but it can be influenced by hydration levels, medications, and kidney function, so it’s less specific. Dizziness can occur with dehydration but has many possible causes, so it isn’t as definitive on its own.