4CPS-101 Successful management of erythromelalgia symptoms with topical ketamine and clonidine: a case report

<h3>Background and Importance</h3> Erythromelalgia (EM) is a rare clinical syndrome that may be associated with myeloproliferative disorders. Due to the incomplete elucidation of its pathogenesis, effective pharmacological management of intermittent triad of symptoms – pain, heat, and redness in the extremities – remains challenging. Despite avoiding precipitating factors such as ambient heat and exercise, patients continue to experience episodic symptoms that significantly diminish their quality of life. <h3>Aim and Objectives</h3> This study aims to review the published evidence on topical treatments for EM and present our single-centre experience through a case study. <h3>Material and Methods</h3> A comprehensive literature search was performed in PubMed using the MeSH headings ‘erythromelalgia’ and ‘administration, topical’ without restrictions on date or publication language. Other resources included Google Scholar and UpToDate. We present data from a 54-year-old female patient with arterial hypertension, diagnosed with a myeloproliferative disorder in 2002 and treated with anagrelide and aspirin. Her initial episodes of erythromelalgia were noted in 2019. The patient‘s medical records were reviewed using the electronic prescribing system, and a treatment plan by a clinical pharmacist was developed in collaboration with a haematologist. <h3>Results</h3> Published literature shows there is a paucity of robust evidence: mainly anecdotal experience or case series that describe topical agents, mainly ointments or patches, with non-steroidal anti-inflammatory agents, lidocaine, capsaicin, gabapentin and combination treatments with ketamine and amitriptyline or clonidine to alleviate EM pain. Topical midodrine, oxymetazoline, brimonidine tartrate, and timolol maleate are also used to reduce redness. Our patient responded well to the compounded combination of amitriptyline 1% and ketamine 0,5% in white vaseline, applied thrice daily. When EM episodes returned in 2024, there was an amitriptyline shortage, and alternative extemporaneously compounded ointment with ketamin 2% and clonidine 0,1% in SydoFarm was prescribed to be applied thrice daily, along with education on nonpharmacological measures such as ice cooling the affected area, limb elevation or fan use. <h3>Conclusion and Relevance</h3> Topical compounded formulations containing combination of ketamine and amitriptyline or clonidine effectively alleviated EM symptoms in our patient, significantly improving her quality of life without significant adverse reactions. Topical agents may be safe first-line treatment for EM symptoms, especially when accompanied by nonpharmacological measures. <h3>References and/or Acknowledgements</h3> Charles University grant SVV 260 665. <h3>Conflict of Interest</h3> No conflict of interest