Those with facial<unk> ing due to ALDH2 deficiency may be homozygotes, with two alleles of low activity, or heterozygotes, with one low-activity and one normal allele. Homozygotes for the trait find consumption of large amounts of alcohol to be so unpleasant that they are generally protected from esophageal cancer, but heterozygotes are able to continue drinking. However, an ALDH2-deficient drinker has four to eight times the risk of developing esophageal cancer as a drinker not deficient in the enzyme. Because most East Asians have a variant in the ADH gene, this risk is lowered somewhat because the ADH variant reduces the risk of esophageal cancer four-fold. However, ALDH2-deficient people who do not carry this ADH variant are at the highest risk of cancer as these risk factors act in a multiplicative manner through increasing exposure time to salivary acetaldehyde. The idea that acetaldehyde is the cause of the<unk>  is also shown by the clinical use of disulfiram (Antabuse), which blocks the removal of acetaldehyde from the body via ALDH inhibition. The high acetaldehyde concentrations described share similarity to symptoms of the<unk> <unk> ing of the skin, accelerated heart rate, shortness of breath, throbbing headache, mental confusion and blurred vision).
Alcohol flush reaction
Cannabinoid hyperemesis syndrome
Alcohol withdrawal syndrome
Post-acute-withdrawal syndrome
Nicotine withdrawal
Drug withdrawal
Poison ivy 
Opioid withdrawal