Sialorrhea is the medical term for excessive drooling. There are many causes of sialorrhea, although the most common cause is difficulty swallowing, either due to a neurologic problem or mechanical problem with the esophagus itself. Excessive saliva can irritate the skin and cause skin breakdown over time.
Physical exam and patient history are generally sufficient. There is no specific test or imaging needed for the diagnosis.
Botulinum A toxin (Botox) is injected into saliva glads to reduce saliva production. The results take 1-2 weeks to reach full effect and last anywhere from 2-12 months. Most patients regularly repeat the procedure when the effect wears off.