You are right that this is most likely to be Acid Peptic Disorder or Acid Reflux. There are several OTC medicines which are generally safe which you can use for this. I would suggest Alka Seltzer two-three teaspoonfuls thrice daily. You should also take Cap. Prilosec 20 mg(OTC) once daily early in the morning.
Besides this, there are some other causes which may cause this.Sinusitis
is the most often implicated cause. Sinus secretions travel down the throat and into the mouth, and this can cause a sensation of slimy feeeling and bitterness.
Any other infection in the mouth, such as tonsillitis
or teeth infections, can also cause such slimy feeling and bitterness.
You should consult a Dentist for this.
A feeling of excess saliva can also be generated due to stress. If you are suffering from stress, you should also discuss with your doctor about anti-stress medications.
THis is certainly not a symptom of any cancer. No cancer will cause such symptoms.
Instead you should try first with the Alka Seltzzer and Prilosec. You are likely to get over this with this two medicines. If not, you should consult a dentist and preferably an ENT(ear, nose and throat) specialist.
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