Erythromelalgia is a rare disease, involving pain, edema, redness, and hyperthermia in the limbs. It is extremely refractory to drugs, has no defined treatment, and causes psychological comorbidities in the patient. We describe a case of erythromelalgia involving a 17-year-old boy who had been suffering from the disease for almost 4 years prior to finding an effective treatment. A bilateral endoscopic lumbar sympathectomy was performed, limited to L2 and L3 resections. Four weeks after the procedure, the patient’s symptoms were significantly mitigated and at 8 months follow-up he remained almost asymptomatic. Endoscopic lumbar sympathectomy was an effective treatment for primary erythromelalgia in this teenager, with exceptional reduction of his symptoms.