First bite syndrome following ipsilateral carotid endarterectomy.

First bite syndrome (FBS) is characterized by unilateral pain in the parotid region after the first bite of each meal, usually following ipsilateral neck surgery. The proposed mechanism is sympathetic denervation of the parotid gland, from iatrogenic injury to the sympathetic trunk supplying this gland. Local botulinum toxin injection has emerged as a promising treatment option with favorable results.