Certain foods, medications and medical conditions cause excessive saliva flow, according to WebMD. Too much saliva is usually not a cause for concern unless it persists.
Spicy, sour and acidic foods cause the body to increase saliva production, explains WebMD. Altering the diet to minimize or exclude these foods potentially prevents this condition.
Medications that sometimes cause excessive saliva production include seizure medicines such as clonazepam, schizophrenia medications such as clozapine, and pilocarpine, which treats dry mouth symptoms in radiation therapy patients. Ingestion of poison sometimes also causes increased saliva production, reports WebMD.
An overactive salivary gland sometimes triggers overproduction of saliva, notes WebMD. Poor muscle control in the face and mouth often causes excessive drooling. Cerebral palsy, Bell's palsy, Parkinson's disease, stroke and amyotrophic lateral sclerosis are some conditions in which excessive drooling occurs.