Alcohol flush reaction is a condition in which a person develops flushes or blotches associated with erythema on the face, neck, shoulders, and in some cases, the entire body after consuming alcoholic beverages. The reaction is the result of an accumulation of acetaldehyde, a metabolic byproduct of the catabolic metabolism of alcohol, and is caused by an aldehyde dehydrogenase 2 deficiency.[4]

“Asian flush” is common in East Asians, with approximately 30 to 50% of Chinese, Japanese, and Koreans showing characteristic physiological responses to drinking alcohol that includes facial flushing, nausea, headaches and a fast heart rate. The condition may be also highly prevalent in some Southeast Asian and Inuit populations.[1][2][3][8]

The most obvious symptom of alcohol flush reaction is flushing on a person’s face and body after drinking alcohol.[4] Other effects include “nausea, headache and general physical discomfort”.[9] People who experience the reaction may be less prone to alcoholism as it tends to discourage them from drinking.