Vascular Disease Patient Information Page: Erythromelalgia

What is erythromelalgia?Erythromelalgia (also known as erythermalgia) is a rare condition in which the feet and/or hands intermittently turn bright red, hot, and painful, especially with exposure to heat.'Erythros' means red, 'melos' means extremity (limb), and 'algia' means pain.Figure 1 summarizes the symptoms, which were first described in the 1870s. 1 Erythromelalgia may be divided into 'primary' or 'secondary' categories.Primary, or idiopathic, erythromelalgia has no clear associated cause or explanation for the condition; inherited erythromelalgia is also considered primary.Secondary erythromelalgia is due to a specific cause or explanation, such as an underlying medical condition or medication.When exposed to warm temperatures or in response to exercise, the blood vessels to the extremities (feet/hands) usually dilate or expand to rid the body of excess heat.This process is called vasodilation.In the case of erythromelalgia, the vasodilation is excessive.The dramatic increase in blood flow causes the affected hands, feet, cheeks, or ears to turn red.The warmth is tied to the sensation of pain, though their exact relationship is not well understood. Who is at risk for erythromelalgia?Erythromelalgia can occur at any age including in children, and it is three times more common among women than men. 1 It is extremely rare, and patients may experience a long delay in diagnosis after seeking consultation with multiple medical specialists.