Heroin Addiction: Short & Long-Term Effects & Risks

Heroin is a fast-acting, illegal opioid drug1 that is highly addictive and can have devastating short-term and long-term health implications, including brain damage, lung complications, infections, and potentially forming a substance use disorder. 

This page will detail the risks associated with heroin use, highlighting specific dangers associated with the different forms of use of the drug, such as injecting, snorting, and smoking. It’s important to keep in mind that many of these health conditions can be mitigated or resolved completely with proper medical intervention and discontinuing heroin use. 

Empowered Recovery Center in Kansas City is an experienced heroin treatment program that has helped many people overcome their heroin addictions, and we can help you establish and maintain a sober life. 

Short-Term Effects of Heroin

Heroin users are often looking to experience the “rush” of feel-good feelings that takes over their brain shortly after using the drug. During this surge of euphoria, the person may experience several other symptoms. The short-term effects of heroin include:1,2

• Dry mouth
• Flushing of skin
• Heavy feeling in arms and legs
• Severe itching
• Nausea
• Vomiting
• Constricted pupils

After the initial spike of pleasurable feelings, the person will often become very tired. During these next several hours, their cognitive function may be lessened, and their heart rate and breathing will slow (sometimes to dangerously low levels).2 

Risk of Heroin Overdose

If a person takes a larger dose of heroin than their body can process, they can experience an overdose. During an overdose, the heroin user’s heart can slow to an extremely faint beat or stop beating entirely. Alternatively, they could stop breathing.2 Without medical intervention, an overdose can be fatal. 

The signs and symptoms of heroin overdose include:1 

• Blue lips or fingernails
• Shallow or slow breathing
• Clammy skin
• Seizures

If you think someone is experiencing a heroin overdose, call 911 immediately. If you have access to Narcan®, administer it, as this medication can reverse an opioid overdose.2 Stay with the person until medical help arrives and be prepared to give information on what type of substance and how much was taken.

Long-Term Effects of Heroin Addiction

If someone chronically uses heroin, they can experience a wide range of serious health complications, including developing an addiction or dependence. These long-lasting effects can impact not only their body, but also their relationships, work, school, and other aspects of their life. 

Long-term effects of heroin can include:2

• Changing the physical structure of the brain 
• Lasting hormonal imbalances
• Pneumonia 
• Tuberculosis
• Sexual dysfunction 
• Irregular menstrual cycles 

Effects of Injecting Heroin 

Many people’s preferred method of using heroin is injection, because of the intensity and speed of effects.3 Injecting heroin comes with its own unique risks that can lead to even more long-term health issues. 

The effects of injecting heroin include:2

• Scarred or collapsed veins
• Abscesses
• Bacterial infections of the blood vessels
• Infections of the heart valves
• Soft-tissue infections
• Infectious diseases like HIV, Hepatitis B, and Hepatitis C from shared needles

Someone who injects heroin may also develop needle fixation, which is when they become addicted to the ritual of injecting as much as the drug itself.4 

Effects of Snorting Heroin

Many people who use high-purity heroin choose to snort it.1 Snorting such a toxic substance can be very damaging to the inner workings of the nose. 

The effects of snorting heroin can include:2

• Damaging the mucosal tissues within the nose
• Causing holes to form in the cartilage or bone between the nostrils

Effects of Smoking Heroin

In some areas, heroin users are switching from injecting to smoking the drug.5 While this does remove some of the risks related to shared injection equipment, smoking heroin still comes with its own serious effects on the body.

Many of the heroin dangers associated with smoking involve the lungs. The effects of smoking heroin can include:6

• Developing COPD
• Developing respiratory morbidity
• Decline in the amount of air being inhaled and exhaled 

How Does Heroin Affect The Brain? 

One of the reasons heroin is so addictive is because of how quickly it reaches the brain compared to other drugs.1 As soon as the drug hits the brain, it binds to and activates receptors called mu-opioid receptors (MORs), which release feelings of pleasure.2 

Experiencing these intense, immediate effects of heroin can lead a person to want to continue taking the drug. Yet, the more a person uses heroin, the more they build up a tolerance to the substance — meaning they need to use more to experience that same level of intensity.1 This, then, leads to a cycle of addiction.

Outside of addiction, heroin effects the brain in several other ways, including:7

• Impaired memory
• Impulse control issues
• Impaired decision-making
• Developing neurological disorders such as toxic leukoencephalopathy and neurodegeneration

How Opioid Receptors Work  

To understand why heroin is so habit-forming, it’s helpful to understand exactly what the drug is doing to our brain and body. Opioid receptors are large protein molecules that receive chemical information from molecules outside the cell.8 These external molecules, called agonists, bind to the opioid receptor to trigger a response, such as feeling pain or pleasure. 

Essentially, think of an opioid receptor as a locked door and agonists as keys.8 When the key is put into the lock, the door is unlocked, and a chemical signal (like pain or pleasure) is released. 

Unfortunately, the agonists aren’t the only “keys” that fit the opioid receptor’s lock. Heroin happens to have a nearly identical structure to natural agonists. This means that heroin can act as a counterfeit key, and when one uses the drug, it triggers more intense feelings of euphoria than a person would experience naturally. 

Heroin Addiction Risk Factors & Causes

There are several factors that may contribute to higher risks of heroin use and addiction. These heroin health risks include how much and how frequently the person is using.9 Using higher doses carries a greater risk of abuse, while even using heroin for a few days can lead to a physical dependence and addiction.9

There are also certain health conditions or characteristics that may lead to a higher chance of addiction. These include being 18-25 years old, having pre-existing mental health disorders, or having a history of substance abuse.9 

Heroin Withdrawal & Treatment

When someone has built a physical dependence on heroin, their body will begin to experience withdrawals if their typical amount of heroin is reduced or stopped altogether. Withdrawal symptoms can occur within just a few hours after heroin is taken,2 which is why some people use heroin continuously to avoid these symptoms. Withdrawal symptoms from regular heroin use can include insomnia, restlessness, muscle pain, diarrhea, vomiting, and cold flashes.2 

When a heroin user begins to experience these uncomfortable symptoms, they are often tempted to begin using again. This is why a medical detox is often recommended when stopping heroin use. In a medically supervised setting, medical professionals can watch over the patient to ensure they’re safe and as comfortable as possible as they go through the detox process.

After the medical detox is complete, the person can dive into treatment for addressing the root causes of their heroin addiction. For some, an inpatient treatment program where the patient lives on-site may be the best option. For others, outpatient options like partial hospitalization or intensive outpatient rehab may be a better choice, as the patient can live at home while still receiving structured treatment. The clinical team can also recommend step-down options for later in their recovery, which could include standard outpatient rehab and aftercare.

Once in rehab, the patient will engage in many different evidence-based addiction treatment methods to learn new coping skills while treating any other co-occurring disorders, such as anxiety, depression, or bipolar disorder. This can be accomplished through different types of therapy, classes around learning new life skills, and medication-assisted treatment (MAT). 

Heroin Rehab in Kansas City

If you’re ready to overcome your heroin addiction and begin to heal from its damaging effects, our team at Empowered Recovery Center in Kansas City can help. We offer a variety of rehab programs in Kansas City that are customized for each patient and specifically designed to give them the best recovery tools.

To learn what our programs all offer, reach out to our rehab admissions team. They can also explain the flexible rehab payment options we provide to our patients, including which insurance plans we can work with. Many of our patients find that their treatment is fully or partially covered by their insurance policy, and our experienced admissions specialists can reach out on your behalf to see what your coverage would include.

Contact us today or verify your benefits online to take the first step toward your recovery from heroin. 

References:

1. Heroin. (n.d.). Retrieved June 11, from https://www.dea.gov/sites/default/files/2025-01/Heroin-Drug-Fact-Sheet.pdf
2. NIDA. 2021, August 3. Overview. Retrieved June 11, from  https://nida.nih.gov/publications/research-reports/heroin/overview
3. Drugs on the Street. (n.d.). https://nida.nih.gov/sites/default/files/mod5_69.pdf
4. Opioids and Injection Drug Use. (n.d.). MN Dept. of Health. Retrieved June 11, from  https://www.health.state.mn.us/communities/opioids/basics/intravenous.html
5. William H. Eger, Daniela Abramovitz, Angela R. Bazzi, Annick Bórquez, Carlos F. Vera, Alicia Harvey-Vera, Joseph R. Friedman, Steffanie A. Strathdee. Changes in injecting versus smoking heroin, fentanyl, and methamphetamine among people who inject drugs in San Diego, California, 2020–2023. (2024, June 1). Drug and Alcohol Dependence Volume 259. Retrieved June 11, from  https://www.sciencedirect.com/science/article/pii/S0376871624002394?__cf_chl_tk=_tyBNAnGrG3Xpus_afpRkcAOvBjs1Zy_tKM_YG4T5bM-1749565292-1.0.1.1-8Qs0lQPywpYqDDayrc7B0IDq2mXreVbSzoRv4fILqi4
6. Rebecca Nightingale, Kevin Mortimer, Emanuele Giorgi, Paul P. Walker, Marie Stolbrink, Tara Byrne, Kerry Marwood, Sally Morrison-Griffiths, Susan Renwick, Jamie Rylance, Hassan Burhan. Screening Heroin Smokers Attending Community Drug Clinics for Change in Lung Function: A Cohort Study. (2020 March). Chest. Retrieved June 11, from https://www.sciencedirect.com/science/article/pii/S0012369219342242
7. Serenella Tolomeo, J. Douglas Steele, Hamed Ekhtiari, Alex Baldacchino. Chronic heroin use disorder and the brain: Current evidence and future implications. (2021, December 20). Progress in Neuro-Psychopharmacology and Biological Psychiatry. Retrieved June 11, from https://www.sciencedirect.com/science/article/abs/pii/S0278584620304644
8. Explainer: how do drugs work? (2016, April 29). The University of Sydney. Retrieved June 11, from https://www.sydney.edu.au/news-opinion/news/2016/04/29/explainer–how-do-drugs-work-.html

Risk Factors for Opioid Misuse, Addiction, and Overdose. (n.d.). DOL. Retrieved June 11, from https://www.dol.gov/agencies/owcp/opioids/riskfactors