Question

Reason for Sneezing Cannot Occurs at Sleep
Sneezing cannot occur during sleep due to _____.

Answer 1

The dust particles come in contact with the membranes (mucus) in the nose.  Due to that the membranes get stimulated and irritated, so we sneeze.

During sleep as smoke and dust particles do not come in contact with the nasal parts, usuallly.  Also the air flow is not brisk and is very soft.   Thus the stimulation of membrane does not occur.

Answer 2

Because during sleep,dust particles do not come in the contact with nasal area