Experiencing strong emotions
Whether it’s fear, frustration, sadness, or excitement, experiencing strong emotions is another weird reason some people sneeze. Being fearful can cause the nasal membranes to shrink, while other intense emotions can cause the nasal membranes to swell.
Both the shrinking and swelling of the membranes can result in sneezing. Similarly, it’s possible for strong emotions to “rub off” on others in groups of bonded friends, leading to even more sneezing.