2 doctors weighed in:

What is the cause of blackouts from heat intolerance?

2 doctors weighed in
Dr. Ed Kaplan
Internal Medicine - Hematology & Oncology
1 doctor agrees

In brief: Dehydration or Vagal

Depends on what you mean.
If stepping into a hot environment suddenly causes you to faint, you may be having a vagal reaction or sudden vasodilation causing pooling of your blood away from your brain. If you are in the heat for a while, you may faint from dehydration and "hypovolemia"

In brief: Dehydration or Vagal

Depends on what you mean.
If stepping into a hot environment suddenly causes you to faint, you may be having a vagal reaction or sudden vasodilation causing pooling of your blood away from your brain. If you are in the heat for a while, you may faint from dehydration and "hypovolemia"
Dr. Ed Kaplan
Dr. Ed Kaplan
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