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Frequently Asked Questions About Rehab

How Do Drugs Affect The Brain?

In essence, when someone starts using drugs, the brain is retrained to not feel as much pleasure unless it has the drug.

What Effects Do Drugs Have On The Brain?

The brain is the most complex organ in the body, constantly firing neurons to make sure we breathe, blink, and continue living. It is responsible for our thoughts and feelings and makes up who we are. It is made up of three major parts: the cerebrum, the cerebellum, and the brain stem, which all work together. The delicate brain is protected by cerebrospinal fluid and the bones of the skull to make sure nothing damages the vital organ. However, sometimes damage can come from within the body and the brain cannot be protected. Medications can save the body and in turn save lives, but when certain medications and drugs are abused, they can wreak havoc on the brain. The way drugs affect the brain can lead to euphoric feelings, but also cause long-lasting damage.

When someone consumes drugs or alcohol, it interferes with the way the brain’s neurons process signals. Drugs can activate the brain’s reward center (basal ganglia), giving pleasurable feelings that people naturally get from sex or eating tasty food. However, drugs over activate the basal ganglia and create intense euphoric feelings. This becomes dangerous when the brain adapts to the presence of the drug and is no longer able to feel pleasure without the drug. Drugs also affect the extended amygdala which plays a role in the anxious, irritable feelings that are associated with withdrawal. Different classes of drugs affect the brain in distinct ways, providing different feelings but also potentially damaging the brain in different ways.

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Stimulants are a class of drug that speed up the body’s systems. It includes prescription medications such as Adderall, Ritalin, Concerta, Anabolic Steroids, and Dexedrine as well as illicit drugs like Cocaine, Ecstasy, and Methamphetamine (Meth). Legal versions of these drugs are intended to treat attention-deficit hyperactivity disorder and narcolepsy, but they are some of the most commonly abused drugs because of their ability to produce energy, attention, and alertness.

Abusing stimulants can negatively affect a user’s life in many ways and leave long lasting damage on the brain. For example, Cocaine users lose twice as much gray matter in a year than non-Cocaine users. Cocaine also changes the shape of neurons and synapses in the brain. When someone snorts, smokes, or ingests Cocaine, the level of dopamine in the brain is increased, giving a pleasurable and satisfied feeling and causing restlessness, energy, and a decreased appetite. Repeatedly flooding the brain with dopamine can damage the structure of the brain, leading to seizure disorders and causing neurons to work slowly or die off.

Methamphetamine is an addictive stimulant that elicits similar effects as Cocaine. Long term Meth use leads to addiction and can change the brain structures that are responsible for decision making. The brain contains non-neural cells called microglia that defend the central nervous system, including the brain, against infectious agents. When there is too much activity of the microglial cells, they start assaulting healthy neurons. According to the National Institute on Drug Abuse, Meth users have more than double the levels of microglial cells, producing a neurotoxic effect that damages the structure and function of the central nervous system.

For Meth abusers, discontinuing use of the drug does not automatically fix everything in the brain. Even years after quitting, previous users can still experience psychotic symptoms such as paranoia, delusions, and hallucinations. Past users of Meth are at a higher risk for developing Parkinson’s disease because of irreversible damage to the brain. However, some neurological damage can be reversed, and microglial activation can get back to a normal state.


Currently America is in the midst of an Opioid epidemic. An average of over 130 Americans die every day as a direct result of an Opioid overdose. This class of drugs, derived from Opium, is primarily used as a pain reliever. Prescription Opioids are very addictive and often lead to people using cheaper, stronger, illegal alternatives such as Heroin and Fentanyl. In a survey of over 11 million adults who misused prescription pain relievers, the main reasons they misused the drug were to relieve pain, change their mood or emotions, and to relax and relieve tension.

The brain has 4 types of Opioid receptors that Opioids attach to, mimicking the production of natural pain-relieving chemicals. Opioids bind to these receptors located in the brainstem, limbic system, and spinal cord, blocking pain. As with stimulants, a user can build up a tolerance to the drug rapidly and then needs a higher dose to get the same result over time. Repeated use of Opioids like Heroin changes the physiology and physical structure of the brain which leaves long term imbalances. Opioid use can damage the brain’s white matter which may play a part in regulating behavior, making decisions, and handling stressful situations.


Central Nervous System (CNS) depressants are used to treat acute stress reactions, anxiety, sleep, and panic disorders. They slow down brain activity and often cause drowsiness. Common types of depressants are Benzodiazepines, Barbiturates, and sleeping pills like Ambien or Lunesta. CNS depressants increase the activity of gamma-aminobutyric acid (GABA) which inhibits brain activity. Long term use of depressants can lead to developing a tolerance and experiencing withdrawal symptoms if they stop taking them. Other long-term effects of depressants include impaired sexual function, breathing problems, convulsions, depression, and insomnia. Too much of a depressant can slow down the heart and potentially lead to overdose and death.

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Inhalants are products that can be easily bought and are often found in an office or home environment. Inhalants include common items such as aerosol sprays, solvents, gases, and nitrites. Aerosols include spray paints, computer cleaning products, vegetable oil sprays, and cosmetic sprays like hair or deodorant spray. Solvents include paint thinners, lighter fluid, gasoline, and glue. Gases that are inhaled include propane tanks, butane lighters, whipped cream dispensers, chloroform, ether, and nitrous oxide. Nitrites may be found in leather cleaner, room deodorizer, or liquid aromas. Inhalants slow down brain activity and produce similar effects as alcohol, such as lack of coordination, feeling high, slurred speech, and dizziness.

Using inhalants can cut off oxygen flow to the brain, resulting in brain damage. Using them can delay behavioral development and cause nerve damage, resulting in loss of coordination and limb spasms. For people who use volatile solvents, studies have shown that the protective sheath around nerve fibers in the brain become damaged and peripheral nervous system damage occurs. This destruction of nerve damage is similar to people with multiple sclerosis. Using inhalants is very dangerous and can cause “sudden sniffing death” where an otherwise healthy person can have heart failure within minutes of inhaling these chemicals.


Although alcohol is legal for people to consume if over the age of 21, its use produces many of the same effects as illicit drugs and is very addictive. It is not difficult to tell when someone is under the influence of alcohol, with signs such as slurred speech and difficulty walking. Long time alcohol abuse can cause permanent damage to the brain and can cause a deficiency of vitamin B1. Some alcoholics develop Wernicke–Korsakoff syndrome (WKS) which is a disease that causes difficulty with motor function, mental confusion, and paralysis of the nerves that move the eyes. Between 80-90% of patients with WKS also get Korsakoff’s psychosis, which causes learning and memory problems.

What Happens To The Brain During An Overdose?

The body will experience an overdose when a toxic amount of drug overwhelms the body and it can no longer cope. In the case of an overdose from Opioids, breathing is affected and the oxygen in the blood decreases, causing lips and fingers to turn blue, and then cutting off oxygen to vital organs like the brain and heart. If the brain does not receive oxygen in 5 minutes, brain damage will begin to occur. Other depressants such as alcohol and Benzodiazepines slow breathing, blood pressure, and heart rate. During a stimulant overdose, the heart rate is increased, potentially leading to stroke, seizure, heart attack, or death. If an overdose is caught quickly, medical attention can often stabilize the patient and save their life.

Prevent Brain Damage From Drugs

The way drugs affect the brain should be taken into consideration when using medications. Using any drug, even as prescribed, can be dangerous. If you or someone you know is putting their life at risk by abusing drugs or alcohol, There is help available. Contact a treatment provider now for more information. The way drugs affect the brain can have serious and life-long consequences, and the best way to protect your mind is to avoid consuming dangerous substances.

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