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Background and Aims Erythromelalgia, a rare disorder categorized as an orphan disease, presents significant diagnostic and therapeutic challenges. The disease manifests in episodic flares characterized by burning pain, erythema, and elevated skin temperature, primarily affecting the extremities, particularly hands and feet. Two etiologies are recognized: primary erythromelalgia, with an autosomal dominant inheritance pattern, and secondary erythromelalgia, which is often associated with underlying conditions such as neoplasms. The pathophysiology of erythromelalgia is likely due to a complex interplay between neural and vascular dysregulation. Unfortunately, most cases demonstrate limited responsiveness to pharmacological interventions, and the efficacy of pain management strategies exhibits substantial variability.

Methods A 69-year-old male with a history of neuroendocrine tumor in the pancreatic tail – surgical removed – and low-risk MGUS of the IgG lambda subtype, was referred to a chronic pain consultation for management of neuropathic pain associated with erythromelalgia. Despite prior trials of various pharmacological interventions, including treatment for the underlying conditions, the patient reported minimal improvement. Application of a capsaicin 8% patch to the hands and feet for a 60-minute duration was proposed as a potential treatment modality.

Results Following the initial application, the patient reported a sustained improvement in both pruritus and burning complaints for a period of six weeks. During treatment, supplementary applications of the capsaicin 8% patch was done with an interval of eight weeks, resulting in further symptomatic improvement.

Conclusions The capsaicin 8% patch emerges as a promising therapeutic modality in the management of secondary erythromelalgia. Notably, each application appears to confer progressively longer durations of pain relief.