Treatment of Frey's Syndrome With "Ready to Use Liquid" Relabotulinumtoxin A (Relfydess).

OBJECTIVE

To describe the off-label intradermal use of ready-to-use liquid relabotulinumtoxinA (Relfydess) for symptomatic Frey's syndrome after parotidectomy.

METHODS

A 72-year-old man with gustatory sweating and flushing after total parotidectomy and adjuvant radiotherapy, who had previously responded to conventional botulinum toxin A, underwent gustatory provocation, clinical mapping, and intradermal relabotulinumtoxinA injections using a 1-cm2 grid. Clinical response and treatment-related adverse events were assessed at 6 weeks and 3 months.

RESULTS

At 6 weeks and 3 months, the patient reported symptom reduction comparable to his previous treatment with conventional botulinum toxin A. At 3 months, repeat gustatory stimulation elicited no visible sweating. No treatment-related adverse events were observed.

CONCLUSION

In this patient, ready-to-use liquid relabotulinumtoxinA provided sustained symptom control for 3 months without observed adverse events. This formulation may offer a practical off-label option for previously responsive patients, while product-specific potency units should not be considered interchangeable.

LEVEL OF EVIDENCE: 5.