Thanks for writing to H.C.M.
I had gone through your query regarding snoring and white foam around your mouth as you find on your awaking in morning.
The snoring occurs whenever there is obstruction in air flow in upper respiratory tract
, as you have already observe about your cold, nasal congestion
, and allergic nose with full of watery discharge and sneezing
You want to be free from snoring so consult ENT doctor to rule out obstructive pathology in upper air way starting from nose to larynx like- DNS, Septal spur, Nasal polyps, Adenoids and enlarge tonsils, Nasopharyngeal mass, Hypertrophied lingual tonsils
, Loose and heavy soft palate, Elongated and tickened uvula and loose and patulus pharyngeal wall. If any of these are detected they can be corrected to make you free from snoring.
If none of above is found than some systemic diseases like Hypothyroidism
, Hyperlipdemia ans obesity should also be considered.
Be on the safe side sleep study is also necessary though you are saying as your sleep is ok.
If you are being unfit for surgical correction or as a pure allergic disorder than C-PAP is the only treatment of choice to make you free from snoring.