sneezing is regulated by the vagus nerve, which also regulates the stomach and heart among other organs. Once I sneezed for half an hour and immediately when it stop I went into Afib.
Applying pressure to your upper lip also stimulates the vagus nerve. Hiccuping is also influenced by the vagus nerve, spasm of the stomach.
I worked with a woman who sneezed exactly three times. She said she was unaware of this. One time she sneezed twice, looked at me, we waited, the third one finally arrived.
I think there are occasions when I could sneeze any number of times. I’ve certainly gone 30 and maybe as many as 50.
I remember reading sneezes can hurt one’s neck, so now I blow my nose. That can be a problem, too.