Hangover – Alcohol Toxicity

Residual alcohol effects, commonly referred to as a “hangover”, occur when the BAC falls to 0 after a heavy binge drinking episode. Unpleasant symptoms usually develop the morning after and can last up to 24 hours. The strength of a person’s hangover largely depends on the amount of alcohol they consumed, type of alcohol they consumed as well as predisposing genetic factors. That being said, some can have one drink and experience a hangover while others will escape the symptoms even after excessive drinking.

Symptoms of a Hangover

Fatigue and muscle weakness
Thirst and dry mouth
Head and muscle aches
Nausea, vomiting and gastrointestinal discomfort
Increased light and sound sensitivity
Shakiness
Deterioration in memory and concentration
Mood imbalances such as depression, anxiety and high irritability
Tachycardia

The severity of a hangover is based on several factors, some of which are listed below.

An infographic that says "The chemistry of a hangover. For most of us, a hangover is the price to pay for a night of drinking. However, we still don't know what exactly it is that causes them. In this graphic, we look at what happens to alcohol in your body, and some of the prime suspects for causing your hangover. Ethanol (ethyol alcohol) to Ethanal (acetaldehyde) to Ethanoate (acetate). What happens to alcohol in your body? In the liver, ethanol is converted to acetaldehyde by the alcohol dehydrogenase enzyme, and then subsequently converted into acetate by the aldehyde dehydrogenase enzyme. Acetate can be broken down into carbon dioxide and water, and then eliminated from the body. On average, the liver can break down alcohol at the rate of one unit (8 grams or 10 milliliters of pure alcohol) every hour. 1. Dehydration - During alcohol intoxication, release of the anti-diuretic hormone (ADH) vasopressin is decreased, resulting in increased urination. Alcohol has a diuretic effect on the body, increasing urine production. Alcohol-induced dehydration has been suggested as a cause for some hangover symptoms, but research suggests it isn't a major factor. 2. Acetaldehyde - acetaldehyde is rapidly converted into acetate in the liver, disulfiram, a drug to support treatment of alcoholism, works by inhibiting the breakdown of acetaldehyde, producing unpleasant, hangover-like symptoms. Acetaldehyde, produced by the breakdown of alcohol, has toxic effects that could cause hangover symptoms. However, acetaldehyde concentration doesn't significantly correlate with hangover severity. 3. Congeners - Methanol is found in very small amounts in many alcoholic drinks. Congeners are compounds other than ethanol in drinks. These include alcohols such as methanol, which breaks down into toxic formaldehyde and formic acid. Congeners can increase hangover severity. 4. Immune System - Cytokines are small proteins released by cells which affect other cells. They play an important role in the immune system. In particular, IL-12 & IFN-y concentration changes show significant correlations with hangover severity. Alcohol causes changes in cytokine concentrations in the immune system. Studies have shown the effects caused by some cytokines are very similar to those of a hangover, strongly supporting their role.
Compound Interest 2016 - www.compoundchem.com, Twitter: @compundchem, Facebook: www.facebook.com/compoundchem
This graphic is shared under a Creative Commons Attribution-NonCommercial-NoDerivatives license. " — Credit

Hangover Culprits

1. Dehydration

Alcohol intoxication inhibits the release of the anti-diuretic hormone, causing frequent urination. Studies suggest that there is an association between alcohol-induced dehydration and common hangover symptoms such as thirst and dry mouth. Although dehydration is not the greatest contributing factor to hangovers, a couple glasses of water will be sure to alleviate some of the unwanted symptoms.

2. Acetaldehyde

In the liver, ethanol is metabolized into its toxic bi-product acetaldehyde and subsequently excreted as acetate. High levels of alcohol intake per hour suppress alcohol dehydrogenase activity leading to the accumulation of acetaldehyde in tissues. Insufficient processing of acetaldehyde in the liver contributes to some of the most common hangover symptoms such as nausea, vomiting and headaches. Disulfiram irreversibly inhibits alcohol dehydrogenase forcing acetaldehyde into the systemic circulation. Disulfiram, commercially known as Antabuse is administered to treat alcoholism because it causes the drinker to get sick enough to give up binge drinking.

3. Congeners

Congeners are biologically active chemicals that are either produced in the process of fermentation or added during the production process to evoke a certain taste, smell and appearance in the beverage. Methanol is a common congener used in the development of dark spirits such as whiskeys and bourbons. Aside from acetaldehyde, methanol or more so, its metabolite formaldehyde is the greatest contributor to hangover symptoms. The human body prioritizes the metabolism of ethanol, so upon finishing ethanol metabolism it proceeds to metabolize methanol into formaldehyde which is why you feel the effects in the morning.

4. Immune System

The immune system can also mediate the severity of a hangover. Studies show that short-term alcohol consumption has an effect on cytokine production. Concentrations of interleukin (IL)-10, IL-12, and interferon-gamma (IFN-γ) were significantly increased during the hangover state. In a recent study, hangover severity was assessed using a self-rating survey. A positive correlation between cytokine production and hangover severity was assessed supporting the theory that the immune system is involved in hangover severity.

Genetics

Researchers found that hangover heritability was upwards of 55%. That being said, genetic factors impact a person’s ability to breakdown alcohol, which is why hangover symptoms vary from person to person. Individuals who have decreased expression of aldehyde dehydrogenase (ALDH) have a higher concentration of circulating acetaldehyde that can elicit uncomfortable symptoms. On the other hand, individuals who have increased expression of alcohol dehydrogenase (ADH) will produce acetaldehyde at a higher rate. Similar to ethanol, fast metabolizers of methanol have greater hangover effects due to increased circulating formaldehyde.