Facial Paralysis-Frey’s Syndrome

Facial Paralysis-Frey’s Syndrome


Frey’s Syndrome (also known as Baillarger’s syndrome, Dupuy’s syndrome, Auriculotemporal syndrome, Frey-Baillarger syndrome) is a rare neurological disorder resulting from damage to or near the parotid glands responsible for making saliva, and from damage to the facial nerve often from surgery.

Symptoms of Frey’s syndrome are redness and sweating on the cheek area adjacent to the ear. They can appear when the affected person eats, sees, dreams, thinks about or talks about certain kinds of food produce strong salivation. Observing sweating in the region after eating a lemon wedge may be diagnostic.

Signs and Symptoms

Erythema (redness/flushing) and sweating in the cutaneous distribution of the auriculotemporal nerve, usually in response to gustatory stimuli. There is sometimes pain in the same area, often a burning nature. Between attacks of pain there is sometimes numbness or altered sensations (anesthesia or paresthesia). This is termed “gustatory neuralgia”.


Frey’s syndrome often results as a side effect of surgeries of or near the parotid gland or due to injury to the auriculotemporal nerve, which passes through the parotid in the early part of its course. The auriculotemporal branch of the trigeminal nerve carries sympathetic fibers to the sweat glands of the scalp and parasympathetic fibers to the parotid gland. As a result of severance and inappropriate regeneration, the parasympathetic nerve fibers may switch course, resulting in “gustatory sweating” or sweating in the anticipation of eating, instead of the normal salivatory response. It is often seen with patients who have undergone endoscopic thoracic sympathectomy, a surgical procedure wherein part of the sympathetic trunk is cut or clamped to treat sweating of the hands or blushing. The subsequent regeneration or nerve sprouting leads to abnormal sweating and salivating. It can also include discharge from the nose when smelling certain food. Rarely, Frey’s syndrome can result from causes other surgery, including accidental trauma, local infections, sympathetic dysfunction and pathologic lesions within the parotid gland.


There is no definitive treatment but various options are described:injection of Botulinum toxin A, surgical transection of the nerve fibers (only a temporary treatment), application of an ointment containing an anticholinergic drug such as scopolamine.





It is a rare complication of facial paralysis.

Lachrymation on the same side of the palsy in connection with stimulation of salivation (when eating)

“Crocodile tears syndrome” is an uncommon consequence of nerve regeneration subsequent to Bell’s palsy or other damage to facial nerve in which efferent fibers from the superior salivary nucleus become improperly connected to nerve axons projecting to the lacrimal glands, causing one to shed tears (lacrimation) during salivation while smelling foods or eating. It is presumed that one would also salivate while crying due to the inverse improper connection of the lacrimal nucleus to the salivary glands, but this would be less noticable.

The mechanism appears to be a misdirection of regenerating gustatory fibers destined for the salivary glands, so that they become secretory fibers to the lacrimal gland and cause homolateral tearing while the patient is eating.