Overactive Saliva Gland Underlying Cause
Saliva production normally increases when the salivary glands respond to certain smells and tastes.
Common causes of excessive salivation include:
- Gastroesophageal reflux
- Infection in the mouth or throat
- Irritation in the mouth
- Medication side effects:
- Dantrium capsules
- Thioridazine hydrochloride
- Motion sickness
- Submandibular gland infection
Less common causes of excessive salivation include:
- Boyce HW, Bakheet MR. Sialorrhea: a review of a vexing, often unrecognized sign of oropharyngeal and esophageal disease. J Clin Gastroenterol. 2005 Feb;39(2):89-97. 
- Hockstein NG, Samadi DS, Gendron K, Handler SD. Sialorrhea: a management challenge. Am Fam Physician. 2004 Jun 1;69(11):2628-34.