vasovagal
Vagus nerve response
Vasovagal describes a response involving the vagus nerve that causes blood pressure and heart rate to drop suddenly, often resulting in fainting.
A vasovagal reaction typically follows triggers like standing too long, seeing blood, or extreme stress: She had a vasovagal episode during the blood draw.
The term appears most often in medical contexts.
Temporary loss of consciousness
- blackoutComplete power loss
- collapseSudden structural failure
- unconsciousnessComplete lack of awareness
- swoonLose consciousness briefly
lightheadedness · dizziness · pallor · sweating · clamminess · nausea · weakness · bradycardia
Nerve system promoting rest
- autonomicSelf-regulating without awareness
- reflexInvoluntary stimulus response
- bradycardiaAbnormally slow heart rate
- vasodilationRelaxation of vessel walls
blood pressure drop · heart rate · baroreceptor · acetylcholine · afferent · efferent · nervous system · cardiovascular
Psychological strain from feelings
- painBodily or emotional distress
- fearEmotional response to threat
- heat exposureContact with high temperatures
- dehydrationExcessive fluid loss
sight of blood · hyperventilation · straining · coughing · urination · defecation · blood draw · medical procedures
fainting
Temporary loss of consciousness
- blackoutComplete power loss
- collapseSudden structural failure
- unconsciousnessComplete lack of awareness
swoon · lightheadedness · dizziness · pallor · sweating · clamminess · nausea · weakness · bradycardia · hypotension
parasympathetic
Nerve system promoting rest
- autonomicSelf-regulating without awareness
- reflexInvoluntary stimulus response
- bradycardiaAbnormally slow heart rate
vasodilation · blood pressure drop · heart rate · baroreceptor · acetylcholine · afferent · efferent · nervous system · cardiovascular · blood pooling
emotional stress
Psychological strain from feelings
- painBodily or emotional distress
- fearEmotional response to threat
- heat exposureContact with high temperatures
sight of blood · dehydration · hyperventilation · straining · coughing · urination · defecation · blood draw · medical procedures · needle phobia
vasovagalcardiac
Pertaining to the heart
cardiogenic · ischemic · arrhythmic · epileptic · myocardial