Frey’s syndrome or auriculotemporal syndrome also termed gustatory sweating typically refers to the phenomenon of increased facial sweating and/flushing after parotid surgery. Botulinum toxin injections have now been accepted as a safe and effective means of treating Frey’s syndrome. As a result other treatment options such as topical and systemic anticholinergic drugs and several surgical options are now rarely used. The study aims to provide a detailed description of the response, dosage and the length of time needed to treat patients with Frey’s syndrome with botulinum toxin treated at our institution.
Materials and methods: A total of 8 patients were diagnosed with Frey’s syndrome post parotidectomy. The diagnosis was both subjective and objective using Minor’s starch iodine test. Each patient was treated with botulinum toxin type A (100 μ Dysport) intradermally to the affected area at four monthly intervals.
Results: All patients responded well. The symptom relief period averaged 6 months. 4 patients required 3 injections before being cured of their symptoms.
Conclusion: Frey’s syndrome frequently occurs after parotidectomy, but it can also arise from other traumatic injuries to the parotid gland. Local intradermal injections of the type A botulinum toxin acts by blocking the release of acetylcholine at the pathologic postganglionic anticholinergic synapses in the sweat glands. The effective duration of botulinum toxin ranges between 10 and 14 weeks, after which axonal resprouting overcomes the medically induced paralysis or weakness, hence the varied treatment responses to the injections.
Key words: botulinum toxin; Frey’s syndrome