Well, sneezing and watery eyes can be due to a reaction to
CPAP machine. This machine dries up the eyes and
nasal passages which causes irritation, burning and sneezing. You can try a cold water humidifier to start with. If you already have a humidifier and you still experience these symptoms you may need a heated humidifier. In most cases this resolves nasal congestion and irritation if it is caused by CPAP. However, its best to consult your specialist.