Pathophysiology: Sympathetic denervation and/or parasympathetic overactivity explain many cases. However, other mechanisms may also exist.
Features of the first bite syndrome:
(1) The sudden onset of intense unilateral parotid pain or cramping in the region of the parotid gland.
(2) Absence of prodromal symptoms.
(3) The symptoms may be triggered by:
(3a) eating (with the first bite)
(3b) use of sialogogues
(3c) salivation
(4) After the initial event repeated stimuli elicit fewer or no symptoms during a given episode.
(5) No other diagnosis can explain the findings better.
Conditions associated with the first bite syndrome:
(1) surgery or trauma to the ipsilateral cervical sympathetic trunk or nerve plexus, especially when there is excision of the superior cervical ganglion
(2) tumor of the ipsilateral parotid or submandibular gland, or in the paraphayrngeal space
Surgeries associated with the first bite syndrome include:
(1) cranial nerve surgery at skull base
(2) cranial nerve surgery in the parapharyneal space
(3) deep cervical lymph node dissection
(4) styloid process surgery
(5) carotid surgery
(6) parotid surgery with ligation of the external carotid artery
(7) resection of the cervical sympathetic trunk
