Red face revisited: Flushing.

The term red face is reserved for lesions located exclusively or very predominantly on the face that result from changes in cutaneous blood flow triggered by multiple different conditions. Facial erythema may not only present clinically as a distinct entity, but can also be a sign of other diseases. Patients with a red face challenge clinicians to consider a broad differential diagnosis. Diagnosis is based on date and mode of appearance, characteristics of the erythema, functional signs, and associated systemic manifestations. In most cases, the cause is a benign disease such as rosacea, contact dermatitis, photodermatosis, and climacterium, and a thorough history and physical examination is enough to make a diagnosis; facial erythema may also present as a symptom of drug allergies, cardiac disease, carcinoid syndrome, pheochromocytoma, mastocytosis, and anaphylaxis, as well as some rare causes such as medullary carcinoma of the thyroid, pancreatic cell tumor, and renal carcinoma where further laboratory, radiologic, or histopathologic studies are required. In this review, the mechanisms of flushing, its clinical differential diagnosis, and management of various conditions that cause flushing are discussed.