Ethnic contact urticaria to alcohol

Aqueous ethnol solutions can induce delayed allergic reactivity in humans, and acetaldehyde and ethanol may show cross-reactivity. In earlier reports of 2 patients with contact urticaria to ethanol, 1 identified as "Vietnamese", it was found that primary but not secondary or tertiary alcohols provoked the reaction. Since primary, and not secondary or tertiary alcohols are converted by alcohol dehydrogenase to the corresponding aldehyde, it is possible that the reaction is really provoked by the aldehyde. Since the current theory on Oriental flushing attributes the reaction a slow aldehyde reductase and subsequent accumulation of acetaldehyde after drinking alcohol. The authors investigated a cutaneous model of this sensitivity. The theoretical basis is strong, since the abnormal aldehyde reductase is found in both cultured skin fibroblasts and hair roots.