Flushing and Blushing
Authors: Keeling Elizabeth , Raghallaigh Síona Ní 
Published: March 2024

Abstract
Flushing and blushing are the result of transient cutaneous vasodilatation that is usually physiological in nature. Although these terms are often used interchangeably, they are distinct processes. A blush signifies a psychosocial response to an experienced emotion, whereas a flush is a thermoregulatory response to increased body temperature. Excessive flushing may be associated with topical agents, food or alcohol intake, or rarely with underlying systemic disease. Clinical features useful in defining the diagnosis include the environmental setting in which the vascular reaction occurs, the extent and pattern of cutaneous involvement, and whether sweating or other systemic symptoms accompany the vasodilatation. Patients with excessive blushing complain of an involuntary and prolonged reddening primarily of the facial skin, which is often precipitated by anxiety, emotion or psychological upset. A flush may evolve in a similar manner to a blush, but often has a more widespread distribution extending to the anterior chest and sometimes the abdomen, particularly the epigastric region. Localised facial sweating may be a feature of flushing. Depending on the underlying aetiology, flushing can be episodic or constant. In patients with longstanding frequent flushing, fixed facial redness and telangiectases may develop. A thorough history, with particular emphasis on precipitating or exacerbating factors, drug and alcohol usage and food intake, and a detailed review of systemic symptoms including queries relating to anxiety and stress, is essential in the evaluation of an individual who presents with a complaint of excessive flushing. Flushing is frequently noted during menopause or in those with rosacea. If an underlying systemic disorder is suspected, a detailed history and clinical examination should help to direct further workup. Initial investigations should include a full blood count, renal and liver profiles, thyroid function tests, urinalysis, 24 h urine for 5‐hydroxyindoleacetic acid (5‐HIAA) (carcinoid syndrome), 24 h urinary fractionated catecholamines and metanephrines, plasma fractionated metanephrines (phaeochromocytoma), serum tryptase, 24 h urine histamine and calcitonin (medullary thryoid cancer). The management of the flushing patient should be tailored to the individual and guided by the underlying cause. However, most flushing patients will benefit from general guidance on managing the flush, such as identification of potential triggering factors (e.g. work environment, temperature, foods, alcohol, drugs) and their avoidance where feasible; information on histamine‐releasing foods and medication; and advice on cooling techniques and temperature regulation. The management of blushing should encompass a comprehensive explanation of the psychosocial nature of the problem and its relationship to anxiety as well as reassurance of the lack of disease association and the possibility of spontaneous improvement in younger patients with time. Topical α‐adrenoreceptor agonists, which produce cutaneous vasoconstriction, have shown efficacy in the treatment of flushing associated with rosacea. Low‐dose β‐blocker therapy may be useful in some patients with either flushing or blushing. Laser techniques such as pulsed dye laser, intense pulsed light and potassium‐titanyl‐phosphate laser may be useful for the treatment of telangiectasia and erythema.