Thanks for sharing your concern.Excessive salivation
is called sialorrhoea.
It can be due to following reasons.
1.Bacterial infections to salivary glands,especially parotid.
2.Certain drugs upon prolonged usage.
3.Any systemic pathology,Various syndromes.
4.viral infection to salivary glands can also cause excessive salivation.
I would advise you to visit your oral surgeon and get your salivary glands thoroughly examined through biochemical tests.
Nature of saliva whether serous or mucous can be confirmed through various test.This will help to understand which gland in affected.
Upon confirmation, suitable treatment can be started.
Hope it helps.