Why Are Drugs Addictive?

It can be tough to understand why someone might be addicted to drugs or alcohol. Friends and family might judge someone with a drug addiction and think they’re lazy or they lack the morals needed to deny themselves another fix. But that’s far from the truth.

A desire to stop using drugs is not enough. For most people, drugs change the way the brain functions. Drug use becomes more than an addiction – it’s a disease. Like most diseases, it can be treated. With proper care, patience and dedication, drug addicts can find healing. Science makes it easier to understand how and why the brain responds to drugs – making it easier to find ways to relieve thousands of people from the addictions that grip them.

What Is Addiction?

The National Institute on Drug Abuse defines addiction as a chronic, relapsing brain disease. It’s an illness that causes the user to seek out compulsive drug use, no matter the harm, pain or other consequences that might follow. While most people make their own choice to use drugs for the first time, the brain conditions itself to the drugs, which will make it more difficult for someone to resist the urges that come with addiction.

Addiction comes with overwhelming cravings that aren’t satisfied until a user takes his or her next hit. Not taking the drug forces the person to go through withdrawal, an often painful, difficult experience.

The brain is an intricate, 3-pound mass that is more complex than we can currently understand. It acts as the control center for the rest of the body. The brain relies on a fine balance of chemicals to carry us through everyday functions – whether it’s our sleep cycle, how we process emotions or the urges for hunger and thirst.

When someone introduces drugs into their system, the repeated process can interrupt the fine balance of chemicals and sensors.

The Cost of Drug Addictions

The negative impact of drug abuse goes beyond that of the user. It can also hurt entire families, communities and society. The overall cost of drug abuse in the United States, including health and crime costs, is $600 billion each year. The breakdown of that overall cost includes tobacco and illicit drugs, but the most substantive amount – $235 billion – is contained in cases of alcohol abuse.

While those numbers are overwhelming, they don’t even touch on the impacts that drug addiction has on job loss, school dropout rates, domestic violence and family separation.

What Makes Drugs Addictive?

A drug is any chemical that makes your body act or function a certain way. Alcohol, caffeine and nicotine are all drugs that enter the bloodstream, travel to the brain and change how it works. By the time a drug gets to the brain, it has the power to disrupt or even change the signals that your brain sends to the rest of your body.


Drugs interrupt the brain by interacting with its neurotransmitters. These chemical substances are released when a nerve impulse gives it instructions. The neurotransmitter travels across the synapse of the brain, sending the message to another part of the body, whether it’s a muscle or nerve fiber. An example of how this works is when you put your hand too close to an open flame. The nerves in your hand send a message to the brain that you’re going to burn yourself. The neurotransmitter delivers that message to your arm muscle, and you jerk back, saving yourself from an injury.

These chemicals are what makes drugs addictive. They work to tell your body that it’s too tired or that it feels pain, but drugs can change that message. Caffeine makes you feel energy when you haven’t had enough sleep. Tylenol relieves the pain of a broken arm.

Drugs can affect the brain in many ways, but addictive drugs usually focus on three main parts of the brain, which are as follows:

  • The brain stem. The brain stem has a big job. It takes control of every function the body needs to perform, including breathing, pumping blood through the veins and turning the food we eat into energy. By linking with the spinal cord, the brain stem is able to control the muscles in arms and legs, as well as send messages back up to the brain about what’s going on in the rest of the body.
  • The limbic system. The limbic system focuses on how we feel. Different parts of the brain control how we respond to certain things, like how good it feels to eat a big bowl of ice cream. Because it feels good, we want to do it again. That’s one way the body naturally encourages us to keep eating to sustain life. Because eating feels good, we keep doing it.
  • The cerebral cortex. The cerebral cortex is the outer edge of the brain that looks like a big gray mushroom. It makes up three-quarters of the human brain and is separated into four different sections called lobes. The lobes control certain functions and help us react. The front of the brain, or the frontal lobe, controls our thoughts and works to help us solve problems, make decisions and plan ahead.

How Drugs Affect the Brain

When drugs enter the body, either by eating, smoking, injecting or inhaling, the chemicals enter the bloodstream and travel to the brain. When the drugs reach the brain, they interfere with its communication and the way cells normally connect with each other.

Different drugs will do different things to the brain. Science gives a better understanding of two major ways that drugs interfere:

  1. Drugs imitate neurotransmitters, or the chemical messengers in the brain.
  2. Drugs heighten the brain’s sense of reward.

Modern science makes it easier to understand what some drugs do once they enter the brain. Marijuana and heroin are structured much like neurotransmitters, often tricking receptors. The receptors let the drug chemicals latch on to them, activating the nerve cells.

Despite tricking the brain, marijuana and drug chemicals don’t react the same way a real neurotransmitter does, so the neurons send mixed messages across the brain, causing a slew of problems.

Cocaine and methamphetamine work differently. These drugs make cells release dopamine, another natural neurotransmitter. Dopamine is a chemical that makes us feel happy. It’s often released after sex or eating. Too much dopamine exaggerates the brain’s messages. Instead of your nerves whispering to each other across the brain, they start shouting in a megaphone. The drug can increase the person’s need for more dopamine to feel satisfied or happy, making them crave more.

This increase in dopamine is what makes people feel “high.” This is also what makes drug addiction so tough to fight. Understanding how different drugs affect the brain helps us better comprehend why drugs are addictive.

Every Drug Is Different

Many illegal drugs today were once used for medical purposes before people realized how addictive or harmful they could be to the body. Let’s look at the different types of drugs and learn why people abuse them.


Stimulants make you feel more alert. They do so by raising levels of nervous or physiological activity in the body. A few of the most commonly abused stimulants are as follows:

  • Nicotine. Nicotine can reach the brain in about seven seconds after it’s inhaled and absorbed through the lungs. Nicotine becomes addictive when it tricks the brain by mimicking acetylcholine, a natural chemical that activates the feeling of pleasure. About nine out of 10 smokers have reportedly said they would like to quit smoking, but feel they can’t. Most people who try to quit report withdrawal symptoms, such as anxiety, being unable to sleep and feeling irritable.After continued exposure to nicotine, the brain starts to rely on the chemical to function.
  • Amphetamine. The Chinese first started using amphetamine extracted from a plant to control asthma symptoms. By the late 1800s, scientists had created amphetamine as a substitute for the brain’s natural chemical, ephedrine. Chemists founds that amphetamine made people more alert and less hungry by increasing dopamine and noradrenaline in the brain.During World War II, soldiers used it to stay awake during long shifts, but it was soon discovered that it had addictive side effects. Today, amphetamine can be found in Ritalin, which is used to increase the attention span in children with attention deficit disorder or hyperactivity disorder. It’s also a derivative of the street drug ecstasy.
  • Cocaine. Cocaine works by mimicking dopamine and noradrenaline in the brain, one of the biggest reasons why drugs are addictive. It gives the user a sense of euphoria, usually making them feel alert. It was first used in the mid-1800s as a miracle drug for patients who suffered from anxiety and depression. It was also used to numb the mouths of dental patients. It was even used in the early versions of Coca-Cola, when cocaine and the caffeine in the kola nut were used to make this popular beverage. Like many other drugs, it was found to be addictive.


Painkillers work by interrupting chemicals in the brain that make you feel discomfort. There are many different kinds of painkillers, many of which can be addictive.

  • Aspirin. Chemists created aspirin in the late 1800s by extracting the natural, pain-relieving elements found in willow bark. Aspirin is usually used to reduce fever and relieve pain associated with inflammation. Aspirin often relieves swelling and stops the chemicals that would tell the brain the body is in pain. Ibuprofen is another synthetic drug that works in a similar way, but doesn’t have as many side effects.
  • Opiates. For thousands of years, the chemicals extracted from the opium poppy flower have been used as a drug. Morphine, named after Morpheus, the Greek god of dreams, is the most addictive aspect of this opiate. A less powerful drug found in opium is codeine. What makes these drugs addictive are their abilities to ease pain, relax the body and make people sleepy. While morphine mimics the body’s natural painkillers, it’s also one of the most addictive substances found today. When doctors tried to lessen the addictive powers of morphine, they created heroin. It was used to relive the common cough when it was first discovered. As it turns out, heroin become one of the most addictive drugs used around the world.The body’s natural opiates are called endorphins. These chemicals are released when someone experiences stress, such as when they exercise.


Sedatives are used to calm someone down. They are used to treat anxiety, depression and to help people sleep. Also known as tranquilizers, sedatives are central nervous system depressants.

  • Alcohol. The oldest and most popular sedative is alcohol. It was used by surgeons during the Civil War to put patients to sleep before procedures. It works by exaggerating some of the chemicals in the brain, making people feel tired and hungry.
  • Barbiturates. While the name might not sound familiar, barbiturates are highly addictive. They are usually used as anesthesia and can only be used in very small, short doses because of their strength.
  • Benzodiazepines. The most common benzodiazepine is Valium. Chemists discovered the drug in the 1950s while looking for a way to treat anxiety. It calms the user without causing drowsiness and works by inhibiting the neurons that control emotions. By 1975, it was the most prescribed drug in the world. Today, doctors limit how often it is prescribed because it’s believed to be addictive if taken over a long period of time.

Why Are Drugs Addictive?

There are many factors that can contribute to addiction. Although we know how drugs affect the brain, it’s difficult to tell how many times someone has to use a drug before getting addicted. For some people, it’s just once. For others, it depends on their genes, where they live and their life struggles. Consider the following factors that can contribute to addiction.

Home Life

Children who are surrounded by people who abuse drugs are more likely to repeat the behavior. Likewise, if people have friends who abuse drugs or alcohol, they can be easily swayed to partake. Students who struggle in school or have trouble socializing have been found to be at a greater risk for using drugs.

Age of Introduction to Drugs

Statistics show that the earlier someone starts using drugs, the more serious his or her addiction can become. Scientists believe this could be because of how harmful drugs can be on a developing brain. Also, addicts who start using one type of drug might begin to experiment with other types of drugs in an effort to seek a greater high.

How the Drugs Are Used

Those who smoke or inject drugs may have a greater risk of addiction because the chemicals reach the brain within seconds, delivering an immediate feeling of pleasure. This kind of high can fade in a matter of minutes, taking the person to a level of depression once the high disappears. Researchers say this drop can make people feel they need to repeat their drug use to try to capture that feeling of pleasure.

Drug Addiction Can Be Reversed

While people recovering from a drug addiction never completely lose the craving for another high, they can reduce that feeling and leave behind their addictive behaviors.

Like other diseases, drug addiction is a healing process that requires long-term treatment and care. Setbacks can happen for someone trying to recover from drug abuse. And if it does, that person needs to reassess their treatment and triggers. Just as people with diabetes might forget an insulin injection or derail from their diet, they can get back on track and lead a healthy life. The same is true for people who wants to change their lives after addiction.

For more information about why are drugs addictive or help for drug and alcohol addiction, contact 12 Keys Rehab today.

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