How Drugs Affect the Brain

How Drugs Affect the Brain

The simple truth is that no one plans to become addicted to drugs. However, the nature of drugs and the way they work on the brain creates the condition that leads to addiction. Drugs begin working on the brain from the very first exposure. Repeated drug use over longer periods of time only worsens addiction and affects the brain in other ways. By learning the way that drugs affect brain chemistry, we can better understand how experimenting with drugs can lead to addiction.

How Does the Brain Work?

The human brain is the most complex and intricate organ in the body. It is the control center of all human activity, including how we think and feel. The brain regulates the body’s basic functions and shapes behavior. Basically, the brain is everything that we are.

The brain is made up of many parts with interconnected circuits that work together. Different circuits coordinate and perform specific functions. Neurons are specialized cells that transmit nerve impulses. The networks of neurons within the brain send signals to one another and among different areas of the brain, spinal cord, and nerves in the body.

When a neuron sends a message to the other areas of the brain, they release a neurotransmitter into the gap between it and the next cell. The neurotransmitter crosses the gap and attaches to the receptors in the brain. This causes a change in the cell that receives it.

How Do Drugs Work on the Brain?

Drugs affect the way that the brain communicates by altering how neurons function. They interfere with the way that neurotransmitters send, receive, and process signals from neurons. Normally, neurons help the brain function and process information. However, when drugs are introduced to the brain, the neurons are over stimulated.

When someone uses heroin or marijuana, for example, the neurons in the brain are activated. This is because the chemical makeup of these substances mimics the brain’s natural neurotransmitters. The similarity of the makeup is enough to activate the neurons, however, they do not transmit in the same way that natural neurotransmitters do. This results in faulty messages being transmitted through the brain.

Other drugs, such as amphetamine or cocaine, affect the brain in a slightly different way. Instead of stimulating the neurons, these types of drugs cause the neurons to release an abnormally excessive amount of the natural neurotransmitters. The brain has trouble keeping up with the flood of neurotransmitters, so it cannot recycle them normally. The brain amplifies the messages it’s sending and results in a disruption of the communication process.


The neurotransmitter most often affected by drugs is dopamine. Dopamine helps to control the brain’s reward and pleasure centers. It also helps regulate physical movement, enables emotional responses, and feelings of pleasure. When drugs cause an excess in dopamine production the brain is sent to a euphoric state, which results in the “high” sensation. This feeling is what compels individuals to recreate the feeling of euphoria by using drugs repeatedly.

Naturally, dopamine is released in situations when we eat something delicious or engage in physical activity. This is an example of a reward that is designed to encourage us to seek out this natural euphoria again. Contrary, drugs multiple the release of dopamine and enhance these euphoric sensations to last much longer than they normally should. This results in the brain telling us to crave and seek out drugs instead. This is why individuals who are addicted to drugs eventually feel flat, lifeless, and depressed. They must continue to use drugs in order to feel a “normal” level of reward.

Long-Term Drug Use and the Brain

The release of dopamine in response to natural high versus the drug high can be compared to a whisper versus a shout. The overproduction of dopamine over a long period of time results in a response from the brain that tries to turn down the shout. The brain reduces the amount of dopamine released under any circumstance in an effort to prevent further flooding of dopamine. As a result, it becomes close to impossible to experience pleasure at all.

This is what occurs when an individual develops a tolerance to a drug. Building up a tolerance to the drug occurs when an individual continuously uses a drug over an extended period of time. This means an individual will have to increase the amount of drug they use just to regain the “normal” feeling. This also prompts the brain to continue restraining the natural release of the neurotransmitter. The cycle continues, worsening addiction.

Over time, this process can have more permanent harmful effects on the brain. Prolonged drug abuse may cause certain behavioral changes. This includes the individual’s ability to maintain self-control, causing them to make impulsive decisions. Drugs also impair judgment, which can lead to self-destructive behavior.

While using substances may create a “feel good” sensation at the beginning, they are ultimately working to alter brain chemistry. As drug use increases and continues, a tolerance is developed. This creates the symptoms that make addiction so harmful and difficult to manage. It’s important to seek professional help and treatment for addiction in order to prevent harmful effects on the brain.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>