Tolerance to alcohol

The marked difference in tolerance to alcohol illustrated by these men is most likely due to a gene encoding which of the following enzymes ... 

Ethanol. As with morphine addiction, tolerance to alcohol is developed, and a lack of ethanol produces withdrawal symptoms. Tire principal route of metabolism of ethanol (both ingested and the small amount of endogenous alcohol) is believed to be oxidation in the liver to the chemically reactive acetaldehyde (p. 774),874/875 which is further oxidized to acetate. Some theories of alcoholism assume that addiction, and possibly also the euphoric feeling experienced by some drinkers, results from a metabolite of ethanol in the brain. For example, acetaldehyde could form alkaloids (Eq. 30-5).876... 

People who drink develop a tolerance to alcohol. Tolerance is the result of the way in which the body handles alcohol as well as alcohol s effect on the central nervous system. A non-alcoholic will have a consistent level of tolerance for alcohol, but an alcoholic s tolerance for alcohol will constantly change, requiring him or her to drink more to get the desired result that lower doses of alcohol had once produced. Tolerance changes the alcoholic s brain impulses, hormone levels, and the chemical make-up of cell membranes. 

Psychological tolerance to alcohol develops at a faster rate than metabolic tolerance. Thus death from alcohol overdose can occur in a psychologically tolerant person following only a moderate increase in alcohol intake above that normally consumed. 

Tolerance to alcohol can be acquired and the point has been made that it costs the regular heavy drinker 2.5 times as much to get visibly drunk as it would cost the average abstainer. This is probably due both to enzyme induction and to adaptation of the central nervous system. 

Intolerance. Inter-ethnic variation in tolerance to alcohol is well recognised, for Asian persons, particularly Japanese, develop flushing, headache and nausea after what are, by Caucasian standards, small amounts of the substance. Genetic deficiency of aldehyde dehydrogenase with slow metabolism of (toxic) acetaldehyde may explain these features. 

A person who has tolerance to alcohol will also demonstrate tolerance to barbiturates the first time he or she uses them. 

Acute tolerance to alcohol s effects-the effects of alcohol at time a are greater than the effects at time b... 

Regular use of alcohol results in some dispositional tolerance (see Chapter 5 for our detailed discussion of tolerance). Therefore, the drinker must consume greater quantities of alcohol in order to maintain a certain BAC. Dispositional tolerance can be reversed with a peritrd of abstinence from alcohol. Functional tolerance has a greater practical influence than does dispositional tolerance in altering how alcohol affects a person with repeated use. Tolerance to alcohol may be both acute and protracted. 

What would be the advantages and disadvantages of creating a definition of legal intoxication" that takes into account an individual s protracted functional tolerance to alcohol ... 

The polymorphism for CYP2E1 is expressed more in Chinese than in Caucasians. Those with the CYP2E1 PM phenotype exhibit tolerance to alcohol and less toxicity from halohydrocarbon solvents. 

It has been suggested that griseofulvin can increase the effects of alcohol, but the descriptions of this response are very brief. One of them describes a man who had a decreased tolerance to alcohol and emotional instability manifested by crying and nervousness, which was said to be so severe that the drug was stopped. Another states that this effect has been noted in a very small number of patients, but gives no further information. 

Ramlov, H., Westh, P. (2001). Cryptobiosis in the eutardigrade Adorybiotus Richtersius) coronifer tolerance to alcohols, temperature and de novo protein synthesis. Zoologischer Anzeiger 240, 517-523. 

Ingram, L. O. (1986). Microbial tolerance to alcohols role of the cell membrane. Trends in... 

Strains of Zygosaccharomyces are known to be extraordinary tolerant to alcohol. Thomas and Davenport (1985) report growth in wines at 18% (vol/vol) alcohol, explaining, in part, the high frequency of isolation from refermenting bottled table wine discussed by Peynaud and Domercq (1959). 

A tolerance to alcohol is developed—Greater amounts must be consumed to obtain the desired effects. Often, the increased tolerance to alcohol is accompanied by increased tolerances to drugs such eis barbiturates. 

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