How the human body can lose tolerance to alcohol if it has not been exposed to alcohol over a long period of time.

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How the human body can lose tolerance to alcohol if it has not been exposed to alcohol over a long period of time.

In: Chemistry

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Anonymous 0 Comments

Various other parts of the body notwithstanding, tolerance to the intoxication that stems from drinking is a very brain-heavy process. Ethanol – the “drinkable” alcohol found in booze – binds mainly to receptors for GABA, a chemical your brain naturally produces in balance with another chemical called glutamate, which excites your central nervous system and makes it more active.

When ethanol binds to GABA receptors, your central nervous system becomes depressed – that is, less active – as though your brain was producing more GABA than it normally would for a given amount of glutamate. This (in large part) produces the feeling of relaxation and the eventual issues with motor contol/speech/etc. associated with getting drunk.

If you drink every once in a while, the effect is pretty pronounced because your brain is otherwise acting normally. When you drink regularly and often, however, your brain begins to produce *more* glutamate than normal because it strives to chemically maintain a balance, and “thinks” there is not enough glutamate to maintain a normal operational state. Over time, this elevated level of glutamate becomes the new “normal,” and so even with the extra GABA-like effects of ethanol you don’t feel as drunk because your brain is now at a higher baseline of excitation.

Just as it takes repetition and regularity to create this state, it also takes a while for your brain to dial things back if you simply stop drinking. Tolerance for the chemical intoxication will gradually decrease, and at some point you will be roughly back to normal.

It is important to note two things, however:

Stopping drinking flat-out leaves your brain overproducing glutamate, which can cause all kinds of problems – what we call alcohol withdrawal. If you drank enough for long enough, this withdrawal can be extremely unpleasant and even life-threatening because an overexcited central nervous system is very bad at managing normal bodily processes.

Additionally, withdrawal from drugs acting heavily on GABA seems to produce an effect called “kindling,” whereby the symptoms of withdrawal get worse as multiple subsequent episodes occur. This can lead to very serious problems with relapsing alcoholics suffering worse withdrawals each time they attempt to stop if they do try to stop cold-turkey.

Anonymous 0 Comments

Here’s my response from your first post that got removed. Not sure if you can see it anymore:

Well, your body is always trying to maintain homeostasis, or a constant healthy state. When you regularly consume alcohol, your body learns this and is prepared to adapt its metabolism of the drug and other things to maintain homeostasis better, even when you’re drunk/high. Essentially your body is trying to keep you from being drunk because being drunk is bad and your body interprets alcohol as a poison.

When you stop consuming alcohol or any drug for an extended period of time, your body sees the substance as “less of a threat” to its homeostasis, and thus lets its guard down and “forgets about it.”