Vasovagal Response Triggered by Sneezing

Classification and Recognition

The European Society of Cardiology categorizes cough and sneeze as established triggers for situational syncope, a subtype of neurally-mediated (reflex) syncope, which includes micturition, defecation, and post-exercise states as other recognized triggers 1
Micturition, defecation, and gastrointestinal stimulation are recognized situational triggers for neurally-mediated reflex syncope 1
Post-exercise and post-prandial states are also situational triggers for neurally-mediated reflex syncope 1

The vasovagal response triggered by sneezing involves sudden augmentation of efferent vagal activity, causing bradycardia, and simultaneous vasodilation from reduced sympathetic activity, leading to peripheral blood vessel relaxation and hypotension 2

Prodromal symptoms, such as nausea, diaphoresis, and lightheadedness, precede loss of consciousness in vasovagal syncope 3
Bradycardia, rather than tachycardia, is a characteristic of vasovagal syncope 3, 2
The absence of pruritus and urticaria helps distinguish vasovagal syncope from anaphylaxis 3
Cool, pale skin, rather than flushed or warm skin, is a characteristic of vasovagal syncope 2

The American Academy of Otolaryngology-Head and Neck Surgery recommends placing the patient supine with legs elevated to restore cerebral perfusion, and observing until symptoms completely resolve, typically within minutes 4, 3
The Centers for Disease Control and Prevention, as published in MMWR Recommendations and Reports, recommend observing the patient for at least 15-20 minutes, as 89% of syncopal episodes resolve within 15 minutes, and monitoring for injury from the fall 4
No epinephrine is indicated unless signs of anaphylaxis are present, according to the American Academy of Otolaryngology-Head and Neck Surgery 3