Heroin is a powerful drug that has an intense impact on brain chemistry. Its side effects can be immediate and devastating, causing long-term cognitive damage that makes quitting the drug very difficult. Understanding how heroin affects the brain is the first step toward healing for individuals and families navigating the road to recovery.
In this guide, we explore the side effects of heroin, the long-term effects of heroin use, and how treatment can reverse the damage.
How Heroin Interacts with Brain Chemistry
Heroin changes the physical structure and functioning of the brain, causing long-term problems with cognitive function and the hormone system. These changes begin with how heroin interacts with certain regions of the brain, disrupting communication pathways and changing the brain’s reward systems.
The Role of Opioid Receptors
After an individual uses heroin, the drug quickly crosses the blood/brain barrier and is converted into morphine. It binds to certain proteins, called mu-opioid receptors, which are located in areas of the brain responsible for regulating pain, pleasure, and reward.
By activating these receptors, heroin causes the brain to flood with dopamine. As a result, the individual experiences feelings of euphoria and well-being. This surge is responsible for the high individuals experience when they use heroin, and it causes them to want to use it repeatedly.
When an individual uses heroin for an extended period, their opioid receptors become less sensitive. The brain has an increasingly difficult time getting pleasure from anything other than the drug. This is one of the main reasons why heroin is so addictive.
Disruption of Natural Neurotransmitter Systems
The long-term effects of heroin aren’t limited to how the drug dulls the brain’s opioid receptors; it also disrupts the balance of transmitters that regulate the individual’s mood, motivation, and stress response.
One of the most significant impacts is on dopamine, a neurotransmitter that’s key to the brain’s reward system. Normally, dopamine is released when the individual is doing something they enjoy, such as eating a good meal, spending time with loved ones, or participating in a favorite hobby. Heroin hijacks this system by causing an unnatural flood of dopamine.
Over time, this repeated overstimulation causes the brain to become far less responsive to dopamine. This means the individual doesn’t get the same amount of pleasure from the things that once brought them joy, and the brain becomes reliant on heroin to feel anything at all.
Heroin also interferes with serotonin and GABA. These neurotransmitters play roles in regulating the individual’s mood and anxiety control. As a result, the individual becomes increasingly emotionally unstable, anxious, and depressed.
These chemical imbalances shed some light on the many side effects of heroin, from emotional numbness to severe withdrawal symptoms. They also highlight how profoundly heroin affects the brain, both structurally and functionally.
Brain Stem Suppression
One of the most dangerous ways heroin affects the brain is by decreasing activity in the brain stem. This is the region responsible for vital automatic functions such as breathing, blood pressure, and heart rate.
When heroin binds to opioid receptors in this region, it slows down the individual’s breathing. This causes hypoxia, or a lack of oxygen reaching the brain, which can lead to respiratory arrest, coma, or death.
Even moderate heroin use can impact the brain stem’s ability to regulate vital functions, especially if it’s combined with other depressants, such as alcohol. This is one of the reasons overdose deaths are so common with this drug.
Short- and Long-Term Brain Changes
Heroin brings about a range of changes in the brain, some of which happen quickly and others that aren’t evident until months or years later. Over time, the brain becomes increasingly reliant on the drug, leading to addiction.
Short-Term Effects on the Brain
Within minutes of heroin use, the drug binds to the opioid receptors and slows down the central nervous system. The individual experiences immediate euphoria and pain relief, but clouded mental function and slowed respiration. These changes show how heroin affects the brain almost immediately, even before the individual becomes physically dependent.
Long-Term Effects of Heroin on the Brain
After prolonged use, heroin causes significant and lasting damage to the brain’s function and structure. Chronic exposure to opioids changes the gray and white matter, impacting areas of the brain that control emotional regulation, decision-making, memory and behavioral control. Long-term use actually causes a reduction in brain volume, especially in the regions of the brain essential for impulse control and reasoning.
These changes contribute to many of the long-term effects of heroin, including an increased risk for mood disorders, cognitive decline and difficulty regulating stress responses.
Tolerance, Dependence, and Addiction
As the brain adjusts to heroin use, it requires more of the drug to achieve the same effect. As a result, the individual becomes physically and psychologically dependent on the drug. For many, casual and occasional use quickly progresses into an addiction.
Cognitive and Emotional Impacts of Use
The changes heroin causes in the brain lead to a significant decline in cognitive functioning. People often experience mental health issues, and their ability to make decisions and build and maintain social connections is diminished.
Mental Health Consequences
Heroin use impacts emotional stability, causing many individuals to experience mood swings, irritability, and symptoms of depression and anxiety. This is especially true for those who have pre-existing mental health conditions. Before an individual begins a heroin detox program, a health care provider conducts a thorough assessment to identify pre-existing or co-occurring mental health disorders.
Impaired Decision-Making and Judgment
As heroin use progresses, the brain’s prefrontal cortex experiences reduced activity. When this happens, individuals often experience a reduced ability to focus, plan ahead, solve problems, and remember new information. These skills are necessary for day-to-day life as well as long-term recovery, highlighting the difficulty of stopping heroin use without professional help.
Emotional Numbness and Social Withdrawal
Heroin doesn’t just affect emotional regulation, but it often dulls emotional experiences altogether. Many people who use heroin long-term report a persistent sense of emotional numbness. This comes from the drug’s suppression of natural neurotransmitter systems, especially dopamine and serotonin.
As the brain becomes dependent on heroin to feel anything at all, things that once brought joy can feel empty and pointless. Individuals lose motivation to spend time with loved ones and invest in relationships. They often find themselves in a cycle of social isolation. Social withdrawal becomes a side effect of heroin use, as well as a coping mechanism.
Reversing Damage Through Treatment and Recovery
It’s clear that heroin has a profound and lasting effect on an individual’s behavioral and brain functioning. While this damage can’t be reversed overnight, those who’ve used heroin can take steps toward healing.
Can the Brain Heal from Heroin Use?
The good news is that research shows that the brain has a remarkable ability to heal itself after heroin use, especially with the right support. This is due to neuroplasticity, or the brain’s ability to reorganize itself by forming new neural connections. When a person stops using heroin, their brain can begin to repair damaged pathways, restore neurotransmitter balance, and improve overall function.
Therapies such as cognitive behavioral therapy, mindfulness practices, and neurofeedback are common in residential rehab programs for those recovering from heroin use because they’ve been shown to support the healing process. Although not all damage is fully reversible, particularly for those who used heroin for a long time, many individuals experience improvements in their mood, cognition and stress regulation within months of beginning recovery.
Medical Detox and Medication-Assisted Treatment (MAT)
Safely stopping heroin use typically begins with medical detox, a carefully monitored program that helps the individual safely and comfortably manage withdrawal symptoms. At FHE, medical professionals provide around-the-clock care and monitoring in a supportive and secure environment.
After detox, medication-assisted treatment is often recommended to help manage cravings, stabilize brain chemistry and reduce the risk of relapse. MAT involves the use of FDA-approved medications such as naltrexone and buprenorphine with naloxone. These medications reduce cravings and block the effects of heroin to help prevent relapse.
Hope and Healing: Life After Heroin
While heroin addiction is powerful, healing is possible. With the right support, brain function can improve, emotional connections can be rebuilt, and the individual can regain a sense of purpose.
At FHE, we provide compassionate care and evidence-based treatment designed to help individuals heal from the damage caused by heroin. No matter how long you or a loved one has struggled, there’s hope. Contact us today to learn about our programs and how we can support the journey to recovery.
