Over 100,000 Americans lose their lives annually as a result of drug overdoses, and another 140,000 are claimed by alcohol. These dire numbers only reflect the most severe aftereffect of using drugs and alcohol. For an additional million more, drugs and alcohol quietly depreciate vital mechanisms in the body long before matters ever become emergencies.
The impacts begin the very first time around. Whether it’s alcohol dilating blood vessels or opioids binding to receptors in your brain, these substances directly alter your body’s usual function. With repeated use, those temporary alterations become irreversible damage, slow down your heart, liver, brain, and virtually every other system organ.
These effects are particularly dangerous because they develop beneath the surface, often without noticeable symptoms until extensive harm has been inflicted. Most people who use drugs like prescription drugs, cocaine, or even alcohol on a daily basis have no idea of the pervasive physical changes taking place in their bodies.
At 12 South Recovery, we’ve helped thousands of individuals recover from the physical damage caused by substances ranging from alcohol to heroin, methamphetamine to prescription medication. Understanding exactly how these substances affect your body provides powerful incentive for seeking treatment and facilitates healing. Let’s examine what occurs in your body when you use drugs and alcohol.
Effects on the Brain and Nervous System
How Substances Alter Brain Chemistry
Your brain relies on a delicate balance of chemicals called neurotransmitters to function correctly. Drugs and alcohol disrupt this balance in ways that can persist long after use stops.
Alcohol enhances the effects of GABA, an inhibitory neurotransmitter that slows brain activity. This explains the relaxation and reduced inhibitions people experience when drinking. Simultaneously, alcohol blocks glutamate, an excitatory neurotransmitter, further depressing brain function. With regular use, the brain adapts by reducing GABA receptors and increasing glutamate activity, leaving the person feeling anxious and unable to relax without alcohol.
Opioids like heroin, fentanyl, and prescription painkillers (OxyContin) bind to specific receptors designed for your body’s natural pain-relieving chemicals. This creates an artificial sense of pleasure and pain relief. With repeated exposure, the brain produces fewer natural endorphins and reduces opioid receptors, leading to tolerance and physical dependence.
Stimulants such as cocaine, methamphetamine, and prescription ADHD medications flood the brain with dopamine, creating intense pleasure and energy. These drugs block the normal recycling process of dopamine, leading to its buildup in the synapses. Over time, this damages dopamine receptors and depletes the brain’s dopamine reserves, making it increasingly difficult to experience pleasure from everyday activities.
Structural Brain Changes
Aside from chemical disruptions, most substances alter the physical composition of your brain. Brain scan research indicates that chronic alcohol consumption reduces the volume of the brain, especially damaging areas that are tasked with memory, decision-making, and motor coordination. This accounts for the intellectual impairments commonly found among chronic drinkers.
Methamphetamine use destroys dopamine and serotonin neurons, some of which never recover even after years of not using. Cocaine constricts blood vessels in the brain, leading to strokes and microbleeds that kill brain tissue. Inhalants destroy the protective myelin sheath surrounding nerve cells directly, disrupting communication between neurons.
Cognitive Function and Mental Health Effects
These physical changes to the brain manifest as significant cognitive and mental health problems. Memory loss, difficulty concentrating, and impaired decision-making become increasingly common as substance use continues. The risk of developing mental health conditions increases substantially, with rates of depression, anxiety, and psychosis all higher among those who use substances regularly.
Marijuana, while often perceived as less harmful, impacts the developing brain particularly strongly. Regular use during adolescence is associated with decreased IQ scores and impaired executive function that can persist into adulthood.
The connection between substance use and mental health represents a two-way street—substances can cause or worsen mental health symptoms. In contrast, many people use substances to self-medicate existing mental health conditions. This relationship underlies the importance of dual diagnosis treatment approaches like those offered at 12 South Recovery, which address both addiction and mental health simultaneously.
Impact on Major Organ Systems
Cardiovascular Damage
Your heart and blood vessels face significant stress from most substances. Stimulants like cocaine and methamphetamine cause immediate increases in heart rate and blood pressure while constricting blood vessels. This combination increases the risk of heart attack and stroke even in young, otherwise healthy individuals.
With repeated use, stimulants can cause inflammation of the heart muscle (myocarditis), arrhythmias, and permanent heart damage. The risk of developing coronary artery disease accelerates dramatically, often leading to heart problems decades earlier than would otherwise occur.
Alcohol initially causes blood vessels to dilate, but ultimately leads to chronic high blood pressure with regular heavy use. Long-term alcohol consumption weakens the heart muscle (alcoholic cardiomyopathy), reducing its ability to pump efficiently. This condition accounts for roughly one-third of all cases of heart failure.
Opioids, while less directly damaging to the heart, create different cardiovascular risks. Intravenous use can lead to endocarditis, a life-threatening infection of the heart valves. Even prescription opioids can cause dangerous heart rhythm abnormalities when taken in high doses.
Liver Function and Damage
As the body’s primary detoxification organ, your liver bears the brunt of processing alcohol and drugs. Alcohol’s effects on the liver follow a predictable progression: first developing fatty liver disease (steatosis), then alcoholic hepatitis (inflammation), and potentially culminating in cirrhosis (permanent scarring). Once cirrhosis develops, the damage cannot be reversed.
Many drugs beyond alcohol stress the liver. Acetaminophen, commonly found in prescription painkillers, becomes highly toxic to liver cells when combined with alcohol. Intravenous drug use significantly increases the risk of hepatitis B and C, which can lead to liver failure. Even some prescription medications can cause drug-induced liver injury with extended use.
Respiratory System Effects
Your lungs and respiratory system suffer particularly from smoked or inhaled substances. Marijuana smoke contains many of the same carcinogens as tobacco smoke. Methamphetamine use is associated with pulmonary hypertension and increased risk of pneumonia. Opioids significantly slow breathing rate, explaining why overdose deaths typically occur through respiratory depression.
Inhalants directly damage the delicate tissues of the lungs and bronchial tubes, while crack cocaine can cause “crack lung”—acute damage to the lungs with symptoms similar to pneumonia. These respiratory effects can persist long after stopping use, with many former users experiencing reduced lung capacity and increased susceptibility to respiratory infections.
Digestive System Disruption
The digestive tract contains numerous receptors that interact with drugs and alcohol. Alcohol directly irritates the stomach lining, increasing acid production and damaging the protective mucosal barrier. This explains the high rates of gastritis, ulcers, and gastrointestinal bleeding among heavy drinkers.
Opioids dramatically slow gut motility, leading to severe constipation that can progress to bowel obstruction if left untreated. Stimulants typically reduce appetite and can lead to significant weight loss and nutritional deficiencies. The lifestyle associated with addiction often involves irregular eating patterns and poor food choices, further compromising nutritional status.
Immune System Suppression
Perhaps most concerning is how drugs and alcohol weaken your immune system’s ability to fight disease. Alcohol disrupts immune pathways, making regular drinkers more susceptible to pneumonia, tuberculosis, and other infections. Their ability to recover from illness and injury is also compromised.
Opioids suppress immune function through multiple mechanisms, while methamphetamine alters the distribution and function of immune cells. People who inject drugs face additional risks of skin infections, abscesses, and blood-borne diseases like HIV and hepatitis.
This immune suppression explains why people with substance use disorders typically experience more frequent and severe illnesses than those who don’t use these substances.
Recovery and Healing
The Body’s Capacity for Healing
Despite the sobering information above, there’s encouraging news: your body has remarkable healing abilities once substance use stops. Many effects of drugs and alcohol can be reversed or significantly improved with proper treatment and sustained abstinence.
Liver function often shows improvement within weeks of stopping alcohol use, provided cirrhosis hasn’t developed. Brain volume can begin to recover after extended sobriety. Cardiovascular health improves as blood pressure normalizes and heart inflammation subsides. Immune function gradually strengthens, reducing vulnerability to infections.
The timeline for recovery varies based on:
- The substance(s) used
- Duration and intensity of use
- Individual health factors
- Quality of medical care and support
This physical healing creates a foundation for psychological recovery, as brain chemistry gradually rebalances and cognitive function improves.
The Role of Professional Treatment
Professional treatment significantly accelerates and supports this healing process. At 12 South Recovery, our approach begins with medically supervised detoxification—creating a safe, comfortable environment for the body to clear toxins while managing withdrawal symptoms.
Following detox, our residential treatment program incorporates medical care and nutrition planning that specifically targets healing from substance-related damage. Regular medical monitoring during treatment helps identify complications requiring additional attention, while our holistic approaches support the body’s natural recovery processes.
For those with significant physical health complications from substance use, our team coordinates with medical specialists to address specific organ system damage. This might include hepatologists for liver issues, cardiologists for heart problems, or pulmonologists for respiratory concerns.
The dual diagnosis approach at 12 South Recovery recognizes that physical healing occurs alongside psychological recovery. Our therapy options—including individual counseling, cognitive behavioral therapy (CBT), and eye movement desensitization and reprocessing (EMDR)—help address the stress, trauma, and mental health factors that often drive substance use and complicate physical recovery.
Family therapy helps rebuild supportive relationships that foster healing. At the same time, our continuing care and alumni programs support long-term recovery, essential for allowing the body sufficient time to recover from substance-related damage.
Call 12 South Recovery Today
The more you understand how drugs and alcohol impact your body, the more you will realize the importance of treatment. The physical destruction wrought by these substances helps explain, in part, why addiction isn’t just an issue of self-control — it’s a deeply ingrained physiological change that requires appropriate treatment in order to heal.
The great news is that tremendous healing is possible with the right support and intervention. We have helped hundreds of people get their physical health back. Our method utilizes medical knowledge alongside evidence-based treatments that are structured to target the bodily and psychological elements of dependence successfully.
If you or someone you care about are struggling with substance use, the good news is that tangible help is out there. At 12 South Recovery, we offer customized treatment plans to facilitate holistic healing, starting with detox and continuing with our outpatient and alumni programs.
Do not allow for another day of damage to accrue. Let us teach you how to restore your mental, emotional, and physical health and heal. If you liked this post, share it with others who might be interested in how drugs and alcohol affect the body.
