Hi.
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain a painful
white patch on the underside of tongue that is present since two weeks seems to be most probably an Apthous Ulcer while
Dry mouth while sleeping is commonly due to
mouth breathing while sleeping..
As the patch is present since 2 weeks still you need not to worry as it will resolve..
But in case of it increase in size and does not resolve in another one week consult an Oral Physician and get evaluated and a
Biopsy can be diagnostic..
For Dry mouth if you have mouth breathing habit you can start sticking a vertical strip of micropore tape so that you start sleeping with closed mouth and you do not suffer dry mouth..
For the white patch apply numbing gel containing Lignocaine over the patch..
Take a Vitamin B complex tablet for atleast 15 days..
Do cool water rinses..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora..