How Drugs Affect the Brain
Overview
The damaging impact of substance abuse can easily be seen in the brain at a very severe level. The brain and nervous system tell the body how to engage with the world and control the body, which includes behavior and feelings.

When foreign substances come into the brain, it can lead to disruption with neuro connectors, resulting in impaired messages being sent. The interaction with different compounds of drugs and activity in the brain can push messages that are false to other parts of the body as well.
Short term physical impact of drug abuse can eventually cause long-term mental issues. The compounds and different chemicals found in drugs begin to control neuronic brain waves, blocking neurotransmitters in the process.
The excess stimulation causes uncontrollable releases of things like dopamine, another chemical strongly associated with pleasurable feelings. Having the right balance of dopamine is extremely important for brain function over a short and long while.
When the brain has a natural balance where substances foreign to the body are introduced, neurons can become dependent on the chemical.
With just one instance of consumption, the body can develop signals that involve having cravings, whereas the brain signals to different neurons that it requires more of the drug’s compounds to work normally.
Drugs impact different areas of the brain. Therefore, consumers of prescription drugs and recreational drugs should understand how they cause harm to the most important organ in the body. Understanding why someone feels cravings and the things that can be done to prevent them are crucial to making a full recovery from drug use.
Knowing what should be combatted can inform patients and doctors about the best tools to combat addictions. Possessing the correct tools will assist patients in their efforts to win over their previous habits.
Various drugs can slow down brain function in some areas but stimulate other areas in excess. Knowing why suppressants and chemical stimulations are risky allows people to understand how dangerous drug use is what it does. When foreign substances come into the brain persistently, they can create permanent physical and mental dependencies that are hard to let go of.
Then there’s physical dependency brought forth from one’s mental state, which coexists with eventual symptoms of withdrawal from someone refraining from the drug. This can happen very quickly with some drugs, even in as little as three months of persistent consumption.
Still, not all hope is lost for addictions that become this extreme. It’s never a bad time for anyone suffering from drug addiction to reverse the damage done to their body and drug addiction. There are specialists throughout the country that specialize in treating addictions.
How Drugs Work
Drugs show their effects by boosting or interfering with the normal functions of receptors and neurotransmitters existing in the synapses of one’s brain. Some neurotransmitters move messages through synapses and others send messages deemed excitatory.

Drugs considered agnostic boost the messages that neurotransmitters carry while inhibitory neurotransmitters become stronger, the same as those which are excitatory.
However, some agonistic drugs can interfere with messages that neurotransmitters send. The usual action that neurotransmitters take is changed to reduce their effects, or outright eliminate them.
There are also numerous other methods in which drugs can boost any number of neurotransmitters. Agonistic drugs can create more production of them. When such neurotransmitters move into synapses, they’re more abundant than they would typically be. More of their substances can find receptors that are postsynaptic using dendrites on new neurons.
Agonistic drugs can also change the reuptake of neurotransmitter particles and can force them to stay in the synapse and stay with receptors for a longer period. Cocaine, for instance, impacts dopamine and norepinephrine systems using this method.
Furthermore, agonistic drugs can move past neurotransmitters completely, floating to synapses and activating their receptors. Additionally, there are other means by which drugs can cause interference with neurotransmitters.
Antagonistic drugs can place neurotransmitters into synapses. They can also bind their receptors, similar to the competition. Antagonistic drugs merge with receptors but don’t cause activation, which blocks neurotransmitters from doing the same.
Antagonistic drugs can make neurotransmitters leak into terminals, and fluid presynaptic neurons, thus making substances from neurotransmitters unable to release into a synapse.
Once neuron activation occurs, a smaller neurotransmitter is available for the synapse than what would have been. The majority of controlled substances that are abused become neurotransmitter agonists, working to boost their natural effect.
The Importance Of Synapses
For one to know the effects that drugs have on the brain, understanding must be made about the way that it’s constructed. In its entirety, the brain is a complex mass of cells that are called neurons, or nerves.

When one produces thoughts, takes an action, or absorbs senses, different neurons send info to each other about what’s being thought about, sensed, or the actions that are taking place. This interneuron way of communication is where drugs have their most impactful effects.
Neurons take the shape of long cells with a slim shape. They consist of three parts, the nucleus, dendrites, and axon. Info moves throughout the neurons beginning inside the dendrites and concluding at the terminal portion of axons.
Alternatively, this is called the button. Neurons take in info with the help of their dendrites, which branch off from them. Neurons grow over time, eventually having their dendrites reach for contact with axons of neurons that are adjacent to them.
Portions of a neuron later have contact with the output portions of other neurons. Axons come from numerous axons, which move toward dendrites in another neuron. The incoming signals, known as excitatory signals, communicate with the neuron so that it can stay in a passive state.
When the excitatory messages become bigger than the signals coming from inhibitory messages, the neuron then becomes active, creating a signal that comes from the neuron’s upper portion and moves down the axon, eventually hitting the terminal. This terminal signal button alerts the dendrites of neurons, which makes the entire process repeat itself.
The nature of signals moving from the different neurons is imperative to understanding how the brain functions. Neurons communicate with one another by way of their interconnected dendrites and axons.
No physical contact is made between one neuron, the terminal button, or the dendrites of others. Instead, the dendrites of an axon have a cavity called a synapse.
When electrical and chemical signals of neurons come to the terminal button, electrical signals halt, which introduces neurotransmitters into synapses. Such chemicals in neurotransmitters move between the synapse and attach with proteins called receptors, which are inside the dendrites of neurons getting the message. These neurotransmitters act as a cipher of sorts, opening receptor locks on the walls of dendrites.
When neurotransmitters spend a short amount of time in the synapse, they release and go back to the terminal button. This process is called reuptake. It makes them stay active in case the neuron must undergo the same process at a later time.
The Neurotransmitters
Here are different chemicals found in the brain that behave as neurotransmitters:
- Dopamine – Regulates movement, punishment, rewards, pleasure, and energy. Drugs such as amphetamines, cocaine, marijuana, heroin, and PCP can effects dopamine found in the brain.
- Epinephrine, or adrenaline – Is a neurotransmitter that’s excitatory and is associated with being alert and excited.
- Norepinephrine, or noradrenaline – Causes alertness, arousal, energy, and pleasurable feelings. Stimulants can affect its activation.
- Serotonin – Regulates impulsiveness and mood. Drugs such as amphetamines, hallucinogens, and depressants are known to activate serotonin levels.
- Acetylcholine – An inhibitory neurotransmitter that’s responsible for memory functionality, movement, sleeping, and will. Marijuana and many hallucinogens can impact this neurotransmitter.
- Gamma-aminobutyric acid, or GABA – This is inhibitory and is responsible for making judgments, making impulsive decisions, and becoming aroused. Depressant drugs and cannabinoids are known activators of GABA.
- Glutamate – An excitatory neurotransmitter, depressants, and opioids can activate glutamate.
- Endorphins – Relative to punishment, reward, and pain relief. As such, opioids and depressants can produce higher levels of endorphins.
Short Term Effects
Drugs can assuredly destroy people, their lives, and the lives of their families. Some people might believe that since someone is given medications as a prescription, they’re safe to take.

However, prescriptions can lead to numerous adverse short-term effects on the brain. People abusing drugs should get help at addiction rehabilitation centers right away.
Getting help sooner for an addiction gives abusers a better chance at overcoming it. This can also make life management much simpler since drug abuse is an expensive habit that can also lead to plenty of legal troubles.
People abusing drugs experience short-term effects regularly. The most common short-term effects are as follows:
- Hangovers – When people think of hangovers, the first image that may come to mind is someone drinking too much alcohol, where a good night’s rest and plenty of healthy fluids would take care of it. There’s no debate about alcohol being potentially abusive but hangovers can also occur with almost every drug, including tobacco. The effects of a hangover can change and alter the brain. They also rid the body of essential vitamins and chemicals found in the brain.
- Withdrawals – Sometimes, withdrawals can be so severe that it places an addicted person into a state that could cause death, especially for opioids and their derivatives. Withdrawals are best handled with professional care, especially for people with an addiction to drugs that are physically addictive.
- Crashing – Crashing can occur with many stimulants. It’s usually from one having an excessive amount of energy, staying up late, then sleeping for long stretches later.
- Anxiety – Anxiety is common in most psychoactive drugs but it is also seen in alcohol and tobacco.
Other short-term effects range from panic attacks, paranoia, hallucinations, and general irritability. Depression and sadness are also common.
Detox programs are recommended for substance abusers before these symptoms are felt. Doing so can prevent them from becoming long-term problems.
Long Term Effects
Plenty of long-term effects can occur with persistent abuse of drugs. Here are the most common:
- Severe depression – Depression at this severity can lead to poor hygiene, lack of motivation, self-harm, and even suicide.
- Alzheimer’s – The onset of Alzheimer’s is often seen in long-term abusers of drugs, which is characteristic of an inability to store information in the brain.
- Schizophrenia – Heavy use of drugs can cause schizophrenia and extreme hallucinations in people, leading to self-harm, harming others, of destructive behavior.
Long-term effects of drug use can be especially damaging to the body and brain. These include physical and mental effects. But long-term effects can go even further, damaging one’s personality, lifestyle, relationships, and many other situations.
Types of Drugs & Effects
Depressants
Depressants include drugs such as Benzodiazepines, alcohol, barbiturates, and similar central nervous system-slowing substances. They act on neurotransmitters called GABA, or gamma-aminobutyric acids. As an inhibitory neurotransmitter, GABA reduces the likelihood of neuron activating.
Depressant substances act as GAMMA agonists, lowering the activation of neurons more efficiently than would typically be done. Additionally, alcohol inhibits excitatory neurotransmitters called glutamate, resulting in difficulty for glutamate to excite the nervous system.
There are also plenty of other effects that alcohol can have on the brain, like lapses in memory and impaired reaction time. It can also progress into long-term harmful changes. Drinking too much is known to shrink the brain. Women are especially at risk of this occurring.

Direct impacts can also be observed from drinking alcohol. Poor nutrition is common in alcoholics, leading to deficiency in thiamine or vitamin B1. In the latest study, it was found that up to 80% of people with an alcohol abuse disorder are deficient in vitamin B1. This can result in lasting damage to the brain. One of the most common is Wernicke-Korsakoff syndrome. The following are characteristics of the illness:
- Nerve paralysis seen in the eye – The eye may become difficult to move around.
- Confusion – Not being able to understand things that previously weren’t an issue comprehending.
- Poor coordination of muscles – Difficulty lifting objects with two hands, holding items with one hand, or keeping items stable without spilling them.
- Learning problems – Memory and learning may become harder to do than it previously was.
Consuming alcohol during pregnancy can cause multiple issues and learning problems, including behavioral changes.
Stimulants
Stimulants include drugs like cocaine, amphetamines, and legal substances such as caffeine. As for amphetamines, they can induce neurons that produce dopamine, allowing more of the substance to be released than what occurs normally.
At the same time, it keeps it away from the synapse longer than what would ordinarily be seen. Amphetamines behave agonistically on neuron receptors, like norepinephrine. It competes with norepinephrine for receptors that are postsynaptic and activates them.
Some stimulants like Adderall can increase performance in people, though stimulant abuse can also lower plasticity in the brain. This can lead to issues with executive function and poor cognitive abilities, along with bad behavioral flexibility over the long term.
It’s very troubling for people that are addicted to stimulants since behavioral flexibility, which is needed to adjust to situations where they take place, is needed to recover from substance abuse. Adolescents and young adults are most at risk for having these changes take place in the brain.
Abusing illegal psychostimulants like cocaine and methamphetamine are closely connected to symptoms like depression. Poor mood and irritability can go back to ordinary levels after the use of such drugs is ceased.
Still, having a hard time feeling pleasure, and reduced motivation can linger in people for long periods of staying sober from drug use.
People that abuse methamphetamine for longer stretches may exhibit symptoms of a psychotic nature, like delusions and paranoia. These may go on for a while after quitting a drug habit. In people that were previous meth abusers, getting into stressful events can trigger psychosis again.
Meth use that occurs chronically can produce brain changes both structural and functional, especially in portions controlling memory and emotions. Similar problems, like flexibility, can also be seen with persistent meth abuse.
Such people in this predicament could have extreme difficulty stopping their habit and engaging in behaviors that aren’t counterproductive. Overall, this makes recovery incredibly challenging.
Opioids
Opioids connect with endorphin receptors found in the brain that control the way one responds to pain. Once activated, sensations of pain cease. Treatments for opioid abuse can involve opioid antagonists like naltrexone. It contains receptors but doesn’t activate them all.
Cannabinoids
Marijuana activates neurotransmitters that control dopamine, acetylcholine, and serotonin. It connects to neurotransmitters called anandamide. Although cannabis is certainly less physically harmful than opioids and meth, it has become more potent than in years past.
High levels of THC can potentially impact the callosum in the brain, which gathers and moves info from the brain’s two hemispheres when needing to process signals for cognitive, sensory, and motor reactions.
Hallucinogens
LSD can block the release of serotonin. Both mushrooms and LSD have the same long-term potential effects on the brain, which is psychosis. It’s characterized by mood and visual disturbances, thinking, paranoia, and anxiety.
References
- https://americanaddictioncenters.org/health-complications-addiction/central-nervous-system
- https://kingswayrecovery.com/rehab-resources/effects-of-drugs-on-brain/
- https://lagunatreatment.com/co-occurring-disorder/prolonged-abuse/
- https://www.addictioncenter.com/addiction/addiction-brain/
- https://www.webmd.com/connect-to-care/addiction-treatment-recovery/how-drugs-affect-the-brain