Alcohol poisoning? Better give you more alcohol.

Why does drinking wood alcohol cause blindness? When would a doctor infuse alcohol for treatment? The answer lies in the fact that there are more types of alcohols than just what we drink.  Alcohol refers to a broad class of chemicals, only one of which is found in beer or wine.

Ethanol is the compound that we are most familiar with. It is a simple molecule consisting of a two carbon chain attached to a hydroxyl group:

The little guy pictured above is the cause of all those great Saturday nights and awful Sunday mornings. Despite how bad ethanol might make us feel the day after imbibing too much of it, our body is pretty good at handling its breakdown (Hangover science).  What the body is not set up for is ethanol's little brother, methanol:

Methanol is the type of alcohol produced by fermenting wood.  The two chemicals might look very similar and both will give you a nice buzz, but methanol ingestion is a medical emergency.  Methanol itself isn't the problem, its what the body does to it that makes it poisonous.  Alcohol dehydrogenase and acetylaldyhyde dehydrogenase, the enzymes that break down simple alcohols, can't tell the difference between the methanol/ethanol and end up poisoning the body.

 

This shows the breakdown of the two molecules. You don't need to know any organic chemistry to see that alcohol dehydrogenase and acetylaldehyde dehydrogenase are doing the exact same thing, just look at the lines.  Alcohol dehydrogenase removes an "H" and adds another bond, or line, to oxygen. Acetylaldehyde dehydrogenase adds an "OH" to the intermediate molecule in both reactions.

In ethanol's case the result is acetic acid, a harmless molecule that can be used for energy.  However, methanol first breaks down into formaldehyde and finally formic acid. Formic acid is nasty. Ants use it to make their stings more potent and in amounts seen with methanol ingestion it destroys the optic nerve causing blindness.

So what can you do for someone that has taken a big swig of wood alcohol? Get them even drunker on the way to the hospital. Alcohol dehydrogenase and acetylaldehyde dehydrogenase both like to work with ethanol much more than methanol.  The trick is to saturate them with ethanol so that they can't break down methanol into formic acid.  The kidneys will slowly filter out methanol before any damage is done.

In fact, an IV infusion of ethanol along with dialysis used to be the preferred treatment in hospitals before the advent of alcohol dehydrogenase inhibitors. These avoid the complications of keeping a patient drunk for 8 hours but they sure take some of the fun out of the treatment.

Hangover Science Time!

Most everyone knows what a hangover feels like, but few know exactly what is going on in the body. "Why does my head hurt?", "Why am I so shaky?", and "Why can't I fall back asleep?" are all common questions that go along with a night out on the town.  Here is a scientific explanation of just exactly how deranged your body becomes after intaking too much alcohol.

Firstly, yes a major part of a hangover is dehydration. Alcohol inhibits a hormone called anti-diuretic hormone. Its what your body releases to tell the kidneys "Hey! stop pissing out all my good water." This is why when you "break the seal" you pee out huge amounts of nice clear urine. The kidneys are not concentrating the urine but are just letting all the fluid that reaches them go to the bladder.

However, you're not going to stop a hangover just by replacing fluids. Alcohol is metabolized into acetic acid, but on its way it becomes something called acetylaldehyde. Acetylaldehyde is the nasty toxin that makes you ache the next day and gives you the water on the brain feeling. How quickly you metabolize this chemical depends on genetics and duration/frequency of alcohol exposure. Many alcoholics don't get hangovers because their body has produced enough metabolic enzymes, called acetylaldehyde dehydrogenase, to clear away this chemical before it affects them. Lots of Asians lack this enzyme and the acetylaldehyde builds up quickly - hence they flush red and feel sick with just a few beers.

Just to hammer this point in, Disulfuram is a medication given to alcoholics to help them control their drinking. It is nothing more than an enzyme that instantly converts alchohol to acetylaldehyde. If someone takes a drink while on disulfuram, instant hangover.

And there's more. Alcohol also inhibits glutamate's effect on the brain. This amino acid is used to by your body to stimulate you and wake you up. When alcohol stops it from working, your body releases a TON of glutamate to make up for it. What sucks is that your body clears the alcohol away faster than the new glutamate. This means that all of a sudden, the extra glutamate you released, plus the glutamate you had before, are no longer being inhibited. This is why you can be tired as hell after a late night drinking but still wake up early and not be able to fall back asleep. Its your body's revenge- "No way you're going to sleep this off, you stay awake and think about what you've done."