What is a primary effect of heat stroke requiring immediate medical attention?

The primary effect of heat stroke that requires immediate medical attention is critical failure of heat regulation. In heat stroke, the body's ability to regulate its temperature becomes overwhelmed, leading to a dangerously high body temperature, typically above 104°F (40°C). This critical failure can disrupt normal physiological processes and result in severe complications, including damage to vital organs, central nervous system dysfunction, and even death if not promptly addressed.

Immediate medical intervention is vital because without it, the body cannot cool itself effectively, increasing the risk of life-threatening consequences. It distinguishes heat stroke from other heat-related illnesses, such as heat exhaustion, where the body's regulatory mechanisms are still functioning but compromised.

While temporary confusion and dehydration are associated with heat-related conditions, they are not the primary life-threatening aspects that necessitate urgent medical care like the complete failure of heat regulation does. Sudden weight loss can occur due to fluid loss but is not an immediate concern compared to the critical nature of heat regulation failure in heat stroke.