Not only gustatory sweating and flushing: Signs and symptoms associated to the Frey syndrome and the role of botulinum toxin A therapy

Abstract

Background The classic symptoms of Frey syndrome are gustatory sweating and flushing. Aims of the study were to describe prevalenceand severity of typical and atypical presentations of the disorder and to assess the effects of botulinum neurotoxin A (BoNT‐A) therapy in patients with Frey syndrome after parotidectomy. Methods In this prospective, observational study on 18 patients, we assessed symptom severity before therapy, after 15 days, 1, 3 and 6 months' follow‐up with the sweating‐flushing‐itch‐paresthesia‐pain (SFIPP) Frey scale specifically designed by the authors themselves for this study. Results Before BoNT‐A injection, all patients (100%) complained gustatory sweating, 80% paresthesia, 77% gustatory flushing, 60% pain and 60% gustatory itch. The SFIPP‐Frey overall score and the symptom‐specific ones decreased significantly at each post‐therapy control. Conclusions The prevalence of “unusual” manifestations is not negligible. BoNT‐A improves symptoms severity. The SFIPP‐Frey scale may be useful to assess symptoms and to monitor post‐therapy outcomes.

Frey syndrome

“…It is described as a local and excessive sweating involving face, scalp or forehead, due to ingesting or smelling specific food products. [43] Those nutrients appear to be carrots, candies, apples, citrus fruits, spicy dishes, coffee and chocolate. [42,43] It may also be useful to distinguish Frey syndrome between allergic reactions.…”

“…[43] Those nutrients appear to be carrots, candies, apples, citrus fruits, spicy dishes, coffee and chocolate. [42,43] It may also be useful to distinguish Frey syndrome between allergic reactions. Differentiating those two conditions, Frey syndrome is often unilateral and allergies are bilateral and nonsegmental.…”

Gustatory Hyperhidrosis

“…Gustatory hyperhidrosis can also be caused by autonomic neuropathy, as in diabetes, and although most often unilateral can also occur bilateral. [1][2][3][4] The latter scenario is difficult to differentiate from idiopathic disease, a rare cause, which was the case in this patient. Gustatory hyperhidrosis may substantially affect quality of life.…”

“…1 Treatment options include injections with botulin toxin A, topical glycopyrrolate, aluminum chloride, oxybutynin, oral anticholinergics, and thoracic sympathectomy. [1][2][3][4] The patient was unsuccessfully treated with oxybutynin. He declined further treatment options.…”

“…This condition, also known as Frey syndrome, most often follows parotidectomy, neck dissection, facelifts procedures, radiation therapy, or facial trauma. Gustatory hyperhidrosis can also be caused by autonomic neuropathy, as in diabetes, and although most often unilateral can also occur bilateral . The latter scenario is difficult to differentiate from idiopathic disease, a rare cause, which was the case in this patient.…”