<unk>  occurs in a warm environment when blood pressure is lowered as the body dilates (widens) arterioles (small blood vessels) in the skin to radiate heat. This condition occurs within five days of heat acclimatization, before the blood volume expands. The result is less blood to the brain, causing light-headedness and fainting when a person stands up quickly or stands for a long period of time. Those who perform strenuous work outside in warm climates are at particular risk.
Heat syncope
Reflex syncope
Laughter-induced syncope
Postural orthostatic tachycardia syndrome
Panic attack
Permissive hypotension
Heat stroke
Reflex asystolic syncope