Alcohol intolerance

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Alcohol intolerance , or alcohol intolerance, describes a disturbed metabolism of alcohol , which can have various causes. Alcohol intolerance often has genetic causes among groups of people in certain regions of the world (for example, some Asians). In addition, alcohol intolerance can occur as a result of excessive consumption and the resulting damage to organs (especially the liver ). There is also the chemical intolerance that occurs when certain medications are taken before or during alcohol consumption.

causes

There are many causes of alcohol intolerance, but usually there is a mutated gene that ensures that insufficient amounts of the enzymes alcohol dehydrogenase (ADH) or aldehyde dehydrogenase 2 (ALDH) are expressed or that the enzymes only work very inefficiently are more unstable. In detail, this happens in ALDH by incorrectly replacing glutamic acid with lysine in the amino acid sequence of the enzyme.

However, since ADH and ALDH are essential for the breakdown of alcohols and their breakdown products, the aldehydes, the mutated gene leads to an increased and only slowly falling acetaldehyde level (if ALDH is affected by the genetic defect) or a slowly falling alcohol level after consumption of ethanol (if ADH or ALDH are affected by the genetic defect).

With the ALDH gene defect, the ethanol can initially be broken down well by the unaffected ADH. The degradation of ethanol only works well until there is too much of the degradation product - in this case acetaldehyde - that cannot be degraded due to the lack of ALDH. Due to the high concentration of acetaldehyde, the ADH can no longer release the newly produced acetaldehyde into the body, but is inhibited by it . As a result, it cannot break down any more ethanol - intolerance occurs. In addition, it can be concluded from this that ALDH-induced intolerance is particularly problematic because, in addition to the slowly falling ethanol level, there is also a very high level of acetaldehyde. Both substances, however, are strong poisons, so the body can be damaged in two ways.

Particularly in groups of people who come from Asian countries, such as Japanese , Chinese , Vietnamese and Koreans , a comparatively high proportion show symptoms of alcohol intolerance.

Certain active ingredients (e.g. isoniazid ) can also reduce the functioning of the liver and thus lead to temporary alcohol intolerance. In contrast to the genetic one, however, this subsides again after the corresponding medication has been broken down (unless there are also breakdown problems on these metabolic pathways, which can occur due to a damaged liver or kidneys).

Symptoms

The following symptoms can occur in various forms of alcohol intolerance:

These are generally the same symptoms that occur in a healthy person after consuming alcohol. However, these are expressed there in a greatly reduced form or only with significantly higher amounts of alcohol.