Info Nugget: Facial sweating during meals? It could be Frey’s Syndrome

What is Frey’s Syndrome?

• A rare neurological disorder also called auriculotemporal syndrome or gustatory sweating.
• Triggered by the abnormal regeneration of nerve fibres post injury near the parotid gland, causing facial sweating and flushing during eating or even thinking about food.
• Named after neurologist Lucja Frey, who described it in 1923.

Why in the news?

• It’s back in attention due to advances in parotidectomy techniques and minimally invasive surgeries reducing its incidence.
• Botulinum toxin treatments are evolving, with studies exploring newer long-acting formulations.
• Also debated in UPSC medical science and ethics papers, given its implications in surgical consent and postoperative quality of life.

Symptoms

• Gustatory sweating: facial sweating, especially on cheek, temple and behind ear, during meals or food thoughts
• Flushing, warmth and sometimes burning sensation or itching
• Typically unilateral, occurs 6-18 months post-injury
• Severity varies; Rs 15 % describe it as “severe”

Causes/risk factors

1. Parotidectomy: most common (Rs 30-50 % incidence)
2. Other surgeries or trauma near the auriculotemporal nerve: submandibular surgery, neck dissection, TMJ repair
3. Rare: inflammation, infections (e.g., mumps), forceps delivery trauma
4. Pathophysiology: Aberrant regeneration of parasympathetic fibres misdirected to sweat glands, instead of salivary glands

Diagnosis

• Clinical history: association with eating, past parotid/neck surgery.
• Minor’s starch-iodine (starch-iodine) test: affected skin turns blue-black during sweating.
• Occasionally use QSART, infrared thermography or salivary gland imaging to exclude other pathologies.

Treatment & management

Conservative/medical

• Lifestyle and dietary adjustment: avoiding spicy, sour meals.
• Topical anticholinergics (e.g., glycopyrrolate), antiperspirants.
• Anticholinergic ointments like scopolamine.

Interventional

• Botulinum toxin A injections: highly effective, lasting 6-12 months, often >90 % symptom relief.
• Surgical options (for severe/persistent cases):
• Neurectomy: cutting aberrant nerve fibres.
• Barrier grafts (fat, fascia, muscle flaps during parotidectomy) – preventive

Prognosis

• Generally benign; may resolve spontaneously in mild cases.
• With treatment, quality of life improves notably.
• Severe cases may need repeat botox or surgical correction.

UPSC civil services perspective

Practice questions

Short-answer (50-100 words)

1. Define Frey’s Syndrome and outline key clinical features.
2. What is the role of the starch-iodine test in diagnosing Frey’s Syndrome?

Long-answer (300-400 words)

3. Discuss the etiopathogenesis, diagnostic methods and management of Frey’s Syndrome in the context of parotid surgeries.
4. Critically examine the role of botulinum toxin A injections in managing Frey’s Syndrome, including alternatives and patient counselling.

Analytical/essay (800+ words)

5. “Frey’s Syndrome exemplifies the importance of surgical ethics and postoperative patient-centred care in otolaryngology.” Critically analyse with reference to its prevention, management and impact on quality of life.