Which symptom is most indicative of heat stroke?

• A. Heavy sweating
• B. Dry, hot skin
• C. Nausea
• D. Altered mental status

Answer: (D)

Heat stroke is a medical emergency marked by very high core temperature with central nervous system dysfunction. Among the symptoms listed, altered mental status most strongly signals heat stroke because brain involvement is a defining feature of this condition and often appears as confusion, agitation, delirium, seizures, or unconsciousness. Heavy sweating is more typical of heat exhaustion, where the body still regulates temperature but is overwhelmed; dry, hot skin can occur with heat stroke but isn’t by itself definitive, since dehydration and other factors can also lead to dry skin. Nausea can accompany many heat-related illnesses but isn’t as specific as changes in mental status. So, when CNS changes are present, they point most directly to heat stroke.