The Chemistry of Addiction

The Chemistry of Addiction

1. Opiates:

Opiates such as codeine, oxycodone and all the way up to heroin and fentanyl, work in the same way.

They work by communicating with our nervous system – our neurotransmitters – telling other transmitters or cells to perform an action.

Now Endorphins are ideal for controlling severe pain as they quite literately communicate through neurotransmitters to prevent cells from being sensitive to pain stimuli.

Endorphins are also released when we exercise, or when we are stressed out emotionally. Ultimately, they make us feel good and can reward us for health activities such as exercising, and helps us cope with high-stress situations.

However, opiates give us such a flood of endorphins that no natural activity can replicate, such is their power.

Therefore, an addict will seek out more and more opiates, to replicate the initial high.
However, our bodies adapt to opiates in our nervous system and create what is known as tolerance. Tolerance is created by our bodies combating the overstimulating effects of drugs and throw a complex array of chemicals at it in an attempt to moderate the effect it is having.

This creates an even bigger problem for addicts who want more of the drug to overcome the tolerance, and thus a dangerous cycle begins.

Interestingly – however – is that the release of endorphins can make people literately addicted to activities exercise and work, in the same way as opiates do.

Of course, when an addict tries to stop opiates, withdrawal symptoms will occur: The brain has been so used to drugs releasing endorphins that when the drug is removed, it now has to re-learn how to release endorphins of its own, which takes time.

It’s during this time where withdrawal symptoms occur: Because we have receptors all over our body, physical symptoms include stomach problems, nausea, joint pain and sweating/chills, while physiological symptoms such as depression and anxiety can linger well after physical symptoms subside.

2. Nicotine

Nicotine takes a different approach at how it causes addiction.

It mimics the neurotransmitter Acetylcholine, which also sets off our ‘reward chemical’ known as dopamine.

But it also releases various other chemicals in addition, including Glutamate.

Glutamate is responsible for us forming memories, and unfortunately when combined with artificial releases of dopamine, it makes a smoker associate smoking a cigarette with feeling a rewarding feeling.

This is critical to why nicotine is such an incredibly addictive drug. It reinforces our memories of how we felt good when smoking, and that effects a smoker’s behaviour.

Habits, such as smoking when drinking alcohol, or smoking after a meal (when dopamine is released) makes us associate these actions with smoking and produces cravings for cigarettes that are difficult to resist.

This tangent of dopamine and glutamate creates a memory loop: This reinforces the addiction because both of these chemicals are both rewarding and is sending messages to transmitters telling us to remember this action, because we will feel rewarded by it in the future.

Of course, all of this is an illusion, and interestingly, all withdrawal symptoms from smoking are psychological. It’s just this tricky ‘memory loop’ is hard to recognise and break, and our brains also have the tendency to associate other activities we were doing when we smoked – like drinking alcohol – and so suffer nicotine cravings when we do these activities alone and not smoking.

3.  Cocaine

Cocaine works by interrupting the reabsorption of dopamine and norepinephrine, essentially meaning that the brain and nervous system is flooded with these two chemicals, and they cannot leave because the brain has trapped them like a dam traps water and creates a reservoir.

This creates a dual effect with the dopamine build up giving the user a sense of euphoria, while the norepinephrine excites all the synapse in the nervous system, giving the user increased energy, hence it’s stimulant effect.

The problem with this is that the Cocaine eventually ends up depleting these neurotransmitters, and thus, users end up taking more and more cocaine in attempt to replicate the initial high.

Eventually this becomes impossible as the cocaine runs out, and the after effects then kick in.

Users will feel the opposite to how they felt whilst on cocaine: Irritated, depressed, fatigued and at times aggressive.

Cravings are often intense as dopamine is depleted to low levels, making the user feel like they need more cocaine.

Therefore, cocaine can create such a vicious cycle that is hard to escape and what makes it psychologically very addictive, despite the fact physical withdrawals are virtually absent.

4. Methamphetamine

Methamphetamine works differently to Cocaine. Instead of interrupting the re-uptake of dopamine and norepinephrine, it simply floods the nervous system with them.

Methamphetamine lasts up to 12 hours because of this action, while a dose of cocaine – typically snorted – lasts a maximum of just 1 hour.

What is particular nasty about methamphetamine is that this excess dopamine it floods the nervous system with is then countered by the body’s defence systems: It sends out various enzymes that destroy this excess dopamine, but this also diminishes the body’s ability to create more dopamine.

This leads to addicts constantly upping their dose to try and achieve that same high, but unfortunately this is all in vain. Eventually the body just cannot release more dopamine and is producing less and less.

This can lead to permanent brain damage in long-term, chronic users, and can even lead to states of psychosis, called “Amphetamine Psychosis”.

Amphetamine Psychosis causes addicts to experience hallucinations, hearing voices, or feeling as if there are insects crawling under their skin. Delusional states are also common, creating paranoia, conspiracy theories or that friends are undercover police.

If addicts are particularly unlucky, this state may linger permanently, but usually they subside within days after stopping their use.

5. Cathinone’s (“Bath Salts”)

This group of drugs came along a few years ago, and they were purposely created by research chemists in order to get around drug laws, as their composition were different to substances that are banned, yet their effects were similar.

However, their mechanism of action is a recipe for disaster.

Like cocaine, they prevent dopamine from being reabsorbed into the system, but at the same time, they tell your neurotransmitters to produce excessive amounts and floods the nervous system with it, just like methamphetamine.

This creates effects that can last literately for days. This means, days without sleep, days being so stimulated a user cannot sit still, days without being able to eat because the appetite is suppressed.

This frequently makes user’s psychotic, to the point that when they were admitted to hospitals not even very large doses of sedatives could calm them down. More frighteningly, only general anaesthetics could actually ‘knock-out’ some users who were in these disturbing psychotic states.

Physical symptoms have manifested in fevers of up to 41.6c, high blood pressure and heart rates, blood toxicity that borders on kidney failure, as well as the psychological symptoms like methamphetamine psychosis, such as paranoia, delusions and hallucinations.

The other scary thing about these drugs is that no one really knows what the long-term effects are, as chemists are creating new analogues all the time to get around laws, so users are essentially human guinea pigs or lab rats.

6. Caffeine

Caffeine is the most widely used psychoactive substance on the planet by quite a long margin.

But despite its popularity, this does not mean it doesn’t cause problems: In fact, very few people realise that it can – technically – cause both psychological and physical addiction. And it’s no joke. The withdrawals from chronic caffeine use can be uncomfortable, but are not life threatening.

So how does it work?

Basically, it tricks our body into thinking that it’s not tired. It accomplishes this because caffeine is extremely like a naturally occurring chemical in our own bodies, called Adenosine.

Bizarrely, though Caffeine is structurally like Adenosine, Adenosine works by bonding to receptors in our brain that slows down our nervous system, which in turn makes us sleepy.

But Caffeine blocks Adenosine before it can bond to receptors, so instead of a calming effect on our nervous system, it stimulates it, exciting the nervous system, increasing heart rate, blood pressure, and alertness.

It has a half-life of 6 hours. So, after 6 hours half the caffeine has left your body. This is why coffee drinkers need to drink coffee throughout the day.

Stopping caffeine abruptly can cause anxiety, irritability and stomach complaints. This can be particularly distressing for those who are predisposed to anxiety.

But the good news is that it’s virtually impossible to overdose on caffeine, as you’d need to drink something like 50-100 cups of coffee to do so, which is physically impossible.

That said, a ‘mild overdose’ can cause extreme anxiety, stomach problems, extreme acid reflux which can be disturbing. However, they will pass without incident, making caffeine a pretty safe drug in the grand scheme of things.

Doctors recommend limiting intake to 2 large cups of coffee per day. Anything above that and it can exacerbate high blood pressure, anxiety or heart problems in those that have these as a pre-existing condition.

7. Alcohol

Found all over the world, and arguably the second most popular drug in the world, alcohol is actually found in nature in fermented fruits.

Alcohol upsets the balance of neurotransmitters that allows body and brain to function as one.

It binds to numerous receptors, including acetylcholine and serotonin, as well as GABA-A receptors.

Serotonin is responsible for several functions throughout the body, including appetite and sleep, while GABA-A is responsible for relaxing us and our nervous system.

As we drink more and more alcohol, the nervous system slows down. We notice this when we start to ‘slur’ our words or communicate more slowly with others.

But after a while, our body builds a tolerance to this by releasing chemicals that excite the nervous systems to try and restore this balance by speeding up transmissions of signals between our neurotransmitters.

The trouble is, when an individual stops drinking the body is full of these excitatory chemicals but has nothing (i.e. the alcohol) to slow it down.

This is why alcohol has very harsh withdrawal symptoms in chronic users, such as shaking hands. Well, the presence of these excitatory chemicals is why this happens.

Luckily, benzodiazepines can make the withdrawal symptoms more comfortable, as they tell the body to release more GABA-A chemicals, which counteracts this nervous excitement. But on the flip-side, using benzodiazepines for more than a couple of weeks can produce an addiction that is also deadly.

8. Gambling Addiction

A number of psychoactive substances have the same mechanism of action to certain behaviours we have.

Gambling on black-jack, horse racing and other games of chance release the same chemicals into our nervous system as the ones that make us learn how to excess reward and risk in natural circumstances.

As hunter-gatherers, we needed to know what types of berry was poisonous and what ones were good for us, and dopamine was released when we picked the correct one, to both reward us and to remind us which one is good and which one is poisonous.

But dopamine is essential for also making us remember the ‘near-misses’. In gambling, this could be missing the jackpot by one number, in which case along with dopamine a number of other chemicals are released into our brain which make us yearn to see patterns.

The problem is, in gambling there are no patterns, and thus this is what makes some of us addicted to gambling.

Gambling addiction is recently being put into the Diagnostic and Statistical Manual of Mental Disorders as a behavioural illness, along with internet porn addiction, sex addictions and eating addictions.

9. Eating Addictions

Eating ‘junk-food’, sugary fatty foods such as chocolate, cheesecake and bacon, releases large amounts of dopamine into our nervous system.

Indeed, in animal studies, rats who were given the option between unhealthy sugary, fatty foods and their normal foods, almost always went for the ‘junk food’, repeatedly. This would continue even when it would make the rats sick and obese.

But overtime, the rats were desensitised to the junk food, and just like in drug addiction, dopamine release was desensitised too.

Research studies such as these has led to theories that some humans just genetically don’t have as many dopamine receptors as other people, which makes them predisposed to certain eating disorders as well as a whole host of other addictions, whether drug or behavioural related.

Of course, being genetically predisposed doesn’t necessarily mean that people with lower dopamine receptors will develop eating problems or drug problems, but it might explain to an extent why some people do, in combination with their childhood upbringing, social status and their overall environment they were born into.

10. Sex Addiction

Like many behavioural addictions such as eating problems, sex addiction has been somewhat ignored and not taken seriously as an addiction due to the stigma surrounding these subjects.

This is unfortunate, because behavioural addictions – as we have explored above – often mimic drug addictions in terms of what is going on with our nervous system.

Sexual orgasms – probably not surprisingly – have been found to release as many endorphins and feelings of subsequent euphoria as a heroin user does when he or she intravenously injects heroin. The rush is essentially the same.

Like eating disorders, sex addiction is related to low levels of dopamine in the brain, which leads a sex addict with a feeling of deep depression and despair after a few hours after having sex, which then leads to him or her trying to find another sexual partner as soon as possible. This is a bit like a ‘sex hangover’.

It is ultimately a craving, both psychologically and chemically, and can cause the sex addict to engage in risky behaviours that can lead to long-term damage, such as sexually transmitted diseases through promiscuous behaviours.

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