Does Heroin Affect the Brain?

Dr. Ximena Sanchez-Samper

Ximena Sanchez-Samper, MD is a Board- Certified Addiction Psychiatrist who obtained her degree as a psychiatrist at the Mayo Clinic in Rochester, MN and completed her Addictions Fellowship through the combined Massachusetts General Hospital, McLean Hospital / Brigham and Women’s Hospital Addictions Fellowship program in 2004.

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How Does Heroin Use and Addiction Affect the Brain?

Heroin, also known as diamorphine or diacetylmorphine, is an opioid substance made from the opium poppy. This substance harms the brain and the body and has been labeled an illegal or controlled substance in several countries worldwide. Heroin is an addictive substance that can lead to dependency after repeated use and could also have adverse psychological effects on the life of the user. 

The long-term effects of using this drug can seriously damage an individual’s health and social and physical well-being. In case you are worried about an individual, knowing the signs and symptoms of heroin addiction is an essential step toward seeking help. 

Signs of Heroin Use

Recognizing the signs of heroin use is crucial for early intervention. These signs can be categorized into physical symptoms, behavioral and emotional changes, and health and hygiene issues.

Physical Signs

Individuals who are just getting started in using heroin will often show physical signs of its use, though they may be subtle. Some of the physical symptoms that an individual is using heroin include constricted pupils, an irregular or slow heartbeat, and drowsiness.

When an individual has a heroin addiction, they tend to lose appetite for food, which leads to rapid weight loss. In the long run, these individuals suffer from nutritional deficiencies that could also lead to other immune-related diseases. Frequent drowsiness or nodding off is a common sign of heroin use. Also known as heroin sniffle, dry mouth and a running nose are other common side effects.

Behavioral and Emotional Changes

Heroin use can cause an individual to become socially distant from others. These individuals tend to isolate themselves from other people even as they prioritize drug-seeking behaviors. It is also possible for them to neglect any responsibilities that they are supposed to undertake.

Individuals who are getting started on heroin may exhibit several behavioral changes. These changes may include being more secretive, losing interest in activities they once enjoyed participating in, and withdrawing from friends and family.

Health and Hygiene Issues

Individuals who use drugs tend to neglect their overall hygiene. They tend to appear disheveled and lose interest in self-care and grooming. Many heroin users inject themselves with needles, which leave track marks on their skin. In most cases, their arms will have scar marks and puncture wounds due to repeated use.

Frequent heroin users and people with addiction tend to neglect their oral hygiene. Some of the common signs with such individuals include gum disease and tooth decay.

Short- and Long-Term Effects of Heroin in the Brain

Since heroin is an addictive substance that causes dependency, its long-term use can lead to adverse effects on the brain as it alters its normal functionality. While the physical effects may appear worrisome, the psychological impact is grave. Here are the short and long-term effects of heroin use on the brain.

Tolerance and Dependence

The continued use of heroin causes an adapting mechanism in the brain. This causes the brain to require increased doses of the substance to achieve the same result. As an individual increases their dosage of heroin, the brain develops tolerance. This, in turn, causes dependence, leading to a repeat cycle.

Restricted Production of Dopamine in the Brain

The body is naturally wired to produce dopamine for feel-good feelings and also to stimulate feelings of motivation and gratitude. Dopamine also helps in controlling moods, sleep, concentration, and memory. When an individual uses heroin, it inhibits the brain’s natural ability to produce dopamine. 

Imbalances in the Brain

Continued heroin use causes the substance to bind itself to receptors known as opioid receptors in the brain. When attaching itself to the receptors, heroin metabolizes into morphine, influencing how the brain and body regulate pleasure and pain. 

Deterioration of White Matter

Heroin addiction can lead to the deterioration of the white matter of the brain. This part of the brain is mostly responsible for aiding communication between the different areas of the brain, and any structural changes affect its overall integrity. 

The individual in most cases will experience challenges in how they regulate their emotions while also experiencing cognitive deficits. The continued use of the substance may also lead to neurological consequences that necessitate treatment to stop the impact on the brain.

Severe Cognitive Impairment

Individuals who are adversely affected by heroin addiction may experience the development of dementia-like body syndrome and severe cognitive impairment. Due to the changes in the brain structure, the individuals develop a condition that resembles Alzheimer’s. 


Chronic heroin use leads to neuroadaptation of a rewiring of the brain. Due to the continued presence of the substance in the body, the brain adjusts itself to produce fewer neurotransmitters. The effect is that an individual will require higher doses of the same substance to achieve the rush they crave. 

Mental Health Issues

Medical research has established that there is a link between mental health issues and heroin use. It is common for individuals who use heroin to develop anxiety and mood disorders and even spiral down to depression.

Hormonal Imbalance

Heroin addiction affects the body’s endocrine system, which, in turn, causes hormonal imbalance in the individual using the substance. The disruption of the normal hormone balance can lead to several physiological and psychological effects. Some of the hormones affected due to heroin addiction include stress hormones, growth hormones, endorphins, thyroid hormones, and sex hormones.

Altered Brain Structure

Continued heroin intake can result in structural alteration of the brain. As an individual gets addicted to heroin, the connections between the brain neurons are lost, leading to the shrinking of the brain. In case an individual stops taking heroin, the shrinking may stop and become reversible, although the damage may remain permanent.

Other consequences that an individual may experience, especially if they are long-term users, include:

  • Blood clots in the injected body parts
  • Lung infections such as TB and pneumonia
  • Liver and kidney damage
  • Infections such as hepatitis and HIV due to needle sharing
  • Stroke
  • Collapsed veins

Psychological Effects of Heroin Addiction

The psychological effect of heroin on the brain is adverse since it is an extremely addictive substance. When an individual uses heroin, it causes a trigger response resulting in the increased production of dopamine. Since dopamine affects the brain’s reward system, it causes an individual to experience a pleasant rush that keeps them hooked on the substance.

Heroin Withdrawal Symptoms

Individuals who are intent on recovering from heroin addiction may experience uncomfortable withdrawal symptoms. In the attempt to stop or reduce the amount of drug intake, an individual will experience withdrawal symptoms as the body tries to adapt to the absence of the substance. The symptoms may vary depending on the duration of use, intensity of withdrawal, and the overall well-being of the individual. Below are some of the notable symptoms of heroin withdrawal.

Vomiting, Nausea, and Diarrhea

Heroin withdrawal comes with gastrointestinal distress, which comes with symptoms such as nausea, vomiting, and diarrhea. This can lead to dehydration or severe complications if not managed properly, hence the need for professional assistance. 

Intense Cravings

Some of the most difficult feelings that an individual recovering from heroin addiction has to contend with are the intense drug cravings they will experience. Due to the dependence levels an individual has reached, the difficulty may vary from one individual to another. During the withdrawal stage, it is important to manage these symptoms for a successful recovery process.

Sleep Disturbance and Insomnia

Insomnia and sleep disturbance are common experiences for individuals during the withdrawal stages of heroin. It is also normal for these individuals to experience vivid dreams and frequent awakenings leading to disrupted sleep and fatigue. Experiencing these symptoms may only worsen the situation for an individual who is already tired and anxious.

Muscle Pain and Twitches

During the withdrawal process, an individual may experience weakness and muscle pain. The body may experience cramping, aching, and overall discomfort.

Anxiety and Depression

Heightened levels of anxiety, restlessness, and depression are major signs of heroin withdrawal. The individuals may experience feelings of agitation and nervousness. The above psychological factors may increase the levels and intensity of social unavailability.

Treatment and Recovery for Heroin Addiction

Detoxing is an effective way for an individual to seek treatment from the effects of heroin addiction. However, undertaking this procedure without supervision can be difficult. Specialized treatment centers offer medical detoxification from trained and qualified professionals with round-the-clock supervision and intervention. After the detoxification process, a physician will work with the individual to create a personalized treatment plan. This is important since each individual is different and the extent of the use differs.

An individual who is addicted to heroin can receive treatment in several different ways. This includes the use of behavioral therapies and medicines. With the advancements in technology, some medicines are being developed for those experiencing withdrawal symptoms. One of these medicines is lofexidine, which is a non-opioid medicine approved by the FDA. 

The heroin addiction medicines work by interacting with the brain receptors, helping reverse the effects of heroin. Some of the ways that individuals can seek treatment for heroin addiction include the following:

Medication-Assisted Treatment (MAT)

Medication-assisted treatment for individuals with heroin addiction include:

  • Methadone – This is an opioid receptor that works by attaching itself to the opioid receptors and activates them as a full agonist.
  • Naltrexone – This is an antagonist opioid receptor that helps protect an individual by attaching itself to the receptors as an antagonist to block heroin effects.
  • Buprenorphine – This is an opioid receptor that acts as a partial agonist. It works by attaching itself to the opioid receptors and activating them to help the individual undergoing the cravings and withdrawal symptoms.

Support Groups

Recovery and peer support groups are instrumental in helping individuals recovering from heroin addiction. The mutual self-help groups offer assistance, guidance, and encouragement. They also offer emotional support while learning new coping skills to identify their triggers, reduce cravings, and ease stress levels. The support groups have varying structures, goals, and social activities. An individual can opt to pursue both support groups and counseling and therapy as they can work hand in hand to help in recovery.

Counseling and Therapy

Therapy is an important tool to assist individuals seeking treatment for heroin addiction. Trained and experienced counselors can also offer much-needed guidance to help these individuals overcome the urge to continue using drugs. Behavioral therapies, such as cognitive behavioral therapy (CBT), together with contingency management, offer an effective approach to help individuals seeking freedom from addiction. The strategies also help in the identification and changing of behavioral patterns contributing to heroin use.

Rehabilitation Programs

One of the best treatment programs for individuals recovering from addiction is seeking help in rehabilitation homes. Depending on the level of heroin addiction an individual has, the levels of care may also vary. Some individuals may require drug detoxification. Several benefits can come out of this strategy, including breaking the addiction cycle, uncovering disorders, gaining healthy habits, and creating healthy boundaries. The rehab programs are instrumental in managing addiction and helping individuals regain sobriety. 

Seeking Help for Heroin Addiction

While seeking treatment for individuals who are addicted to heroin, it is important to approach them with empathy and understanding. It is important to encourage these individuals to seek professional help. Undertaking a comprehensive approach to treatment increases the chances that an individual will successfully recover from the addiction. 

For those seeking comprehensive and empathetic treatment for heroin addiction, Charles River Recovery offers a supportive and professional environment. Our center provides personalized treatment plans, encompassing medication-assisted treatment, therapy, and support groups tailored to the unique needs of each individual. Reach out to our team today for more information about our treatment services.