 [ Symptoms ] i read that you need a some sunshine on your bare skin to get enough vitamin d so why should i use a sunscreen [ Disease ] i use my cpap when i have a cold but it is important to make sure your airway nasal airway with my cpap is open i use saline nasal spray and some nose blowing but even then my nasal passage may become compromised in the middle of the night the cpap will not cause sinusitis but certainly colds can set the stage for a secondary sinus infection especially if you are prone to them