Withdrawal is a painful process that happens
after someone stops taking a mind-altering substance, but why exactly is it so miserable? Withdrawal of any kind of substance can be
harrowing and exhausting. Some of the most dramatic symptoms include nausea, sweating,
shaking, and even hallucination. So what’s going? Why does withdrawal wreak such havoc
on the body? First, let’s talk drug addiction in general.
There’s lots of different substances you can become addicted too. While opioids are
the most well known additive substances, alcohol and caffeine addictions are common too. You can get hooked on these substances because
they alter the release of neurotransmitters and change the way the brain works…sometimes
with pleasing results. But after long term exposure to a drug, the brain tries to restore
normal functioning through adaptations. This is what building up drug tolerance is. If
this goes on for a long time, the user becomes dependent, needing the drug to maintain just
normal functioning and avoid withdrawal symptoms. When that user goes off a drug, the brain’s
compensation is still in place, leading the brain to be more active in certain areas.
This leads to what’s called withdrawal syndrome. Withdrawal symptoms can develop in 24 hours
and last anywhere from a week to months on end. There’s lots of different mechanisms that
create dependency and withdrawal. One example is how opioids affect a brain chemical called
noradrenaline. Opioids are known to cause drowsiness, slowed respiration, and low blood
pressure. This is because opioids suppress the neurons that produce noradrenaline. Over
time, with opioid dependence, the body counteracts this suppression by releasing more of the
chemical to support these functions at normal level. But, even if a user stops taking the drug,
the body still releases an elevated level of noradrenaline…which produces withdrawal
symptoms like jitters, anxiety, muscle cramps, and diarrhea. Similarly to how opioids affect noradrenaline,
alcohol affects production of another brain chemical called GABA, which governs neuron
activity. Too little GABA, and neurons fire rapidly. You feel excited, hyper, thoughts
are flying around a mile a minute. Too much GABA and neurons subside a bit. You feel calmer,
more relaxed. Sometimes too much, like stumbling around, slurring words kind of sedated. So
you can guess which alcohol does, yeah it increases GABA. Chronic alcohol use impairs the ability of
GABA to calm the brain down. So more GABA, and thus more alcohol is needed to get the
same relaxing effect. And once alcohol intake stops, GABA levels drop dramatically. Which
makes the brain overreact. And that can lead to things like teeth-chattering, uncontrolled
shaking, jumpiness, and even seizures…that last one can even be deadly. While you might think withdrawal doesn’t
apply to you… put that coffee down. I know most of you probably drink it. According to
New Scientist, it’s the world’s most popular drug.
But go without it for a day and you might experience a headache, tiredness, feeling
low, foggy, less sociable, and even feeling like you’ve got the flu. Caffeine works on the receptors for the neurotransmitter
adenosine. Adenosine facilitates sleep by calming the brain down. Caffeine sneaks in
there and binds to adenosine receptors, so it blocks adenosine from doing it’s job.
That’s why you perk up with a morning cup of Joe. Drinking caffeine regularly can also
increase the number of adenosine receptors in the brain. So you need more caffeine to
get the same effect, or in other words, you build up a tolerance. But caffeine also causes your brain to release
dopamine, so you tend to feel good after your morning coffee. Then once you stop drinking
coffee, you crash because suddenly your body is without the feel good boost and anti-sleepiness
of the caffeine. Thankfully, withdrawal from caffeine only lasts a few days. One drug that’s incredibly addictive and
deadly is heroin, yet it’s use in the US is on the rise. What makes heroin so deadly?
Find out more in this episode right here.