Alcohol intolerance

Alcohol intolerance is due to a genetic polymorphism of the aldehyde dehydrogenase enzyme, which is responsible for the metabolism of acetaldehyde (produced from the metabolism of alcohol by alcohol dehydrogenase). This polymorphism is most often reported in patients of East Asian descent. Alcohol intolerance may also be an associated side effect of certain drugs such as disulfiram, metronidazole, or nilutamide. Skin flushing and nasal congestion are the most common symptoms of intolerance after alcohol ingestion. It may also be characterized as intolerance causing hangover symptoms similar to the "disulfiram-like reaction" of aldehyde dehydrogenase deficiency or chronic fatigue syndrome. Severe pain after drinking alcohol may indicate a more serious underlying condition.

Drinking alcohol in addition to consuming calcium cyanamide can cause permanent or long-lasting intolerance (nitrolime disease), contributing (in conjunction with other substances) to the accumulation of harmful acetaldehyde in the body by inhibiting the acetaldehyde dehydrogenase enzyme.