Negative results of hard drinking: the biochemistry of hangovers.

Hangover –noun--

the disagreeable physical after-effects of drunkenness, such as a headache or stomach disorder, usually felt several hours after cessation of drinking.

Black, but not quite. The kind of black you see from the inside of your eyelids. You’re fully awake but drowsy nonetheless. You can’t concentrate on anything. Mouth and throat are dry. Dizzy. Stomach possibly still turning. Nausea, and anxiety. Brain swimming in your skull - directionless and no where to go. Blood thundering through your ears.

You were fine six hours ago when the alcohol was swimming around and permeating your blood system. Bizarrely enough, now your blood alcohol content has returned to zero you start to feel the effects. The ethanol you’ve ingested has been metabolised to acetaldehyde by alcohol dehydrogenase, mainly in the liver, and then converted into acetate by mitochondrial aldehyde dehydrogenase in many tissues, including brain tissue. And this is when you feel like death. Our best understanding puts acetaldehyde as the cause of the hangover. But it gets more complicated than that.

Popular belief states that the cause of hangover symptoms is simple dehydration. Dehydration is a migraine trigger in some people, and increased water intake has been proposed as a preventive treatment. The holy grail of the hangover cure. In reality, it’s a lot more complicated than that. Alcohol hangover and dehydration seem to be two independent yet co-occurring processes that have different underlying mechanisms. There are a whole host of biochemical changes associated with the Hangover. Endocrine parameters (increased concentrations of vasopressin, aldosterone, and renin) and metabolic acidosis (reduced blood pH values due to increased concentrations of lactate, ketone bodies, and free fatty acids) to name just a few.

Presence and severity of alcohol hangovers are influenced by many factors other than the amount of alcohol. Top among the list is the presence of congeners in alcoholic drinks - the substances that colour and flavour drinks.

The hangover headache is the most common and symptom following a night out. The mechanism of veisalgia cephalgia or hangover headache is unknown. Despite a lack of mechanistic studies, there are a number of theories placing - along with congeners - dehydration or the ethanol metabolite acetaldehyde as causes of hangover headache. Several factors do not cause alcohol hangover but can aggravate its severity; including sleep deprivation, smoking, health status, genetics and individual differences. Not to mention the difference between brandy and vodka; red and white wine, containing sulphites, tannins, phenols, and other compounds involved in the increase plasma levels of serotonin and histamine, associated with causing the hangover headache. Complicated enough to give you an actual headache.

Acetaldehyde has long been viewed as the prime suspect of the hangover, but new research now implicates acetate, the next metabolite in the pathway in the general mechanism. The levels of acetate in the serum is rapidly elevated past that of acetaldehyde. Add to this several key facts:

• Acetate causes ethanol induced hypersensitivity
• Caffeine blocks ethanol induced hypersensitivity
• Ketorolac blocks ethanol induced hypersensitivity

The increase in acetate increases adenosine in many tissues, including the brain, overstimulating adenosine receptors and contributing to your headache. The adenosine receptor antagonist, caffeine, given after ethanol ingestion in rats, blocked the pain from nerve stimulation associated with ethanol. Caffeine and ketorolac are commonly used to treat hangover symptoms in humans. Non-steroidal anti-inflammatory drugs (ketorolac) alleviate the headache pain associated with alcohol hangovers and caffeine is indicated to ease other hangover symptoms, including fatigue and malaise.

Hangover effects are a difficult thing to experiment on. Due to the simple nature of being unable to blind such experiments. Alcohol intoxication and its after-effects are impossible to mimic by a placebo condition. Disentangling the many factors involved in the onset of the hangover is very important to elucidate the actual physiological response to ethanol. To avoid the long-term negative effects of alcohol, an alcoholic needs to get alcohol abuse help the soonest possible time.

What’s the best cure or remedy for an alcohol induced hangover?

Prevention.

Written by Dr. Charles Ebikeme for The All Results Journals.