Long-Term Effects of Drugs on Brain Functionality


Our brain is a complex organ, and the effects of drugs on brain functionality are similarly complicated.

There are short-term and long-term effects of drugs on brain health and function.

These effects lead to addiction, dependence, mental health issues, heart attacks, a lapse in memory, and more.


Initial Effects of Drugs on Brain Functionality

When someone initially takes a drug, it impacts the communication between their neurons.

Then, the drugs can activate neurons.

Some drugs, such as heroin, can activate neurons because they have a similar structure to natural neurotransmitters.

While some drugs replicate brain chemicals, they don’t activate neurons the same way, so messaging becomes abnormal.

Then, other drugs such as stimulants like cocaine and amphetamine can cause neurons to release abnormally high amounts of neurotransmitters; this also disrupts communication.

When someone takes a drug, it creates euphoria.

That’s known as being high.

It probably occurs because of the surge in neurotransmitters stimulated by the drug.

So when someone takes a drug, it can release amounts of neurotransmitters much higher than would be associated with ordinarily pleasurable activities.  

Dopamine is one neurotransmitter that can highlight the effects of drugs on brain function.

  • When someone takes certain drugs, their brain releases dopamine in response.
  • Our brains want to repeat activities that create pleasure.
  • Drugs activate the reward cycle because of the dopamine flood they lead to.
  • The dopamine signaling makes it easier to continue repeating a pleasure-creating habit without thinking about it. That leads to habits, or in some cases, addictions.


Areas of the Brain Affected by Drugs

  • Basal ganglia: This part of the brain is important for motivation and creating habits and routines. This is also known as the “reward circuit.” Drugs over-activate this part of the brain. Over time, this part of the brain may not be as responsive to the effects of the drug, and it can also be more difficult to experience pleasure from everyday activities. 

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  • Extended amygdala: This brain region mediates feelings of stress, and it’s relevant to withdrawal symptoms a person might experience after they stop using a drug or after the high fades. With repeated exposure, a person with a substance use disorder may continue using them to avoid feeling discomfort rather than getting high. 
  • Prefrontal cortex: This part of the brain involves decision-making and impulse control. Someone with a substance use disorder might compulsively seek out the substance and have less impulse control because of the effects of drugs on the prefrontal cortex. 

Long-Term Effects of Drugs on the Brain

In general, there can be significant long-term effects of drugs on the brain.

For example, ongoing drug use and addiction can raise the risk of developing certain mental health disorders, including anxiety and depression.

Specific long-term effects of drugs on the brain can include:

  • Impaired cognitive function. Glutamate is a neurotransmitter that also plays a role in the reward system and is affected by drugs. When the brain tries to make up for the changes caused by drugs, it can make it harder to learn and think.
  • Memory function. Ongoing drug use can impact learning and memory.
  • Brain connections: There are physical changes in the brain, mainly related to the links between neurons.
  • Brain cell death. Drugs are toxic to brain cells, and this damage is permanent.

While some of the brain damage from drug use is irreversible, if you stop using drugs, your brain can start to adapt and begin to function normally once again over time.


How Opioids Affect the Brain

Opioids are one of the most commonly misused classes of drugs.

They are known as central nervous system depressants, and doctors prescribe opioids as pain relievers; there are also illicit opioids such as heroin.

When someone uses opioids, they bind to receptor sites throughout the central nervous system.

They change how messages are sent to the brain. That’s how they are effective at combating pain.

Opioids also slow down the functions of the CNS, which can include breathing. Short-term effects of opioids include euphoria, drowsiness, and fatigue.

Long-term effects of opioids can include hallucinations, anxiety, and depression.

It’s also possible to develop extreme sensitivity to pain because of how opioids affect pain receptor sites in the body.

The longer someone takes opioids, the more pronounced the effects of the drugs on brain function will be.

For example, you can become dependent on opioids. Then, when you stop using them, you may go through withdrawal.

Withdrawal is one of the most common long-term effects of drugs.

Symptoms of opioid withdrawal can include anxiety, irritability, insomnia, runny nose, vomiting, and cramping.


How Meth Affects the Brain

Methamphetamine is another drug of abuse. In the short term, someone might experience a rush of energy, confidence, talkativeness, and euphoria when using meth.

Meth is a stimulant, which is why those are some of the short-term effects.

Chronic meth use can lead to dependence and symptoms of withdrawal.

Other long-term effects of meth may include:

  • Anxiety
  • Insomnia
  • Violence
  • Mood disturbances
  • Confusion
  • Psychotic symptoms like delusions and hallucinations

The psychotic symptoms that can occur with chronic meth use may last for months or years after someone stops using it.

In studies looking at the brains of long-term meth users, researchers have found both structural and functional brain changes in the areas linked to emotion and memory.

In addition, in animal studies, meth appears to affect the structures in the brain responsible for decision-making.


How Marijuana Affects the Brain

Support for marijuana legalization is growing, but that doesn’t mean it’s safe to use, particularly for young people.

THC is the psychoactive component of marijuana. When a person takes marijuana, brain receptors react to the THC it contains.

As a result, someone feels high because of the activation of specific receptors in the brain.

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The short-term effects of marijuana can include:

  • Altered senses, such as seeing colors differently
  • Problems with thinking
  • Changes in the sense of time
  • Mood changes
  • Memory impairment
  • In high doses, marijuana can cause hallucinations, delusions, and psychosis

There are long-term effects of marijuana on brain development when teens and young people use it.

Research shows that marijuana use by teens and young people can have long-lasting effects on memory, learning, and thinking.

For example, there was a New Zealand study conducted in conjunction with researchers from Duke University.

People who began heavily using marijuana as teens lost an average of 8 IQ points between the ages of 13 and 38.

Long-term marijuana use, regardless of age, has also been associated with a higher risk of mental illness in some people.

This could include temporary paranoia or hallucinations, depression, anxiety, and suicidal thoughts.

Final Thoughts

The effects of drugs on brain function can be severe, and they can be challenging to reverse.

The short-term impact on the brain can include euphoria, changes in levels of neurotransmitters, and even addiction.

The long-term effects of drugs on the brain can include everything from changes in structure and function to an inability to experience pleasure without drugs.

Luckily, even though some changes brought about by drugs may technically be irreversible, the longer someone is sober and abstains from using them, the more their brain can heal and normal function can start to return.

Opus Health offers many services that can help with healing brain functionality, from detox to nutritional plans.

If you or a loved one is concerned with the long-term damage caused by drug addiction, contact Opus Health today to create a plan of action. 

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