What Are the Effects of Heroin?

Heroin is a potent, fast-acting illicit opioid drug made from the opium poppy plant.^{1, 2} The Drug Enforcement Administration (DEA) classifies heroin as a Schedule I substance, indicating that it is not accepted for use in any medical treatment in the United States, has a high potential for abuse, and is not safe to use even under medical care.² Heroin is highly addictive and can negatively impact a person’s life.²

If you or a loved one are struggling with heroin use, this article will help you understand more about heroin’s effects, including:

• Side effects of heroin.
• Heroin withdrawal symptoms.
• Risks of injecting heroin.
• How heroin affects pregnancy.
• Signs of a heroin overdose.
• Treatment for heroin addiction.

Short-Term Effects of Heroin

When people use heroin, it binds to opioid receptors in the brain, which are involved in regulating feelings of pain, pleasure, and reward.^{1, 3} Shortly after using heroin, a person will experience a strong sense of pleasure, or euphoria, known as a “rush,” accompanied by feelings of well-being and drowsiness.¹

The opioid receptors that heroin acts on are involved in regulating breathing, pulse, and sleep.^{1, 3} The speed of onset and intensity of heroin’s effects can vary depending on how it is taken and the dose, but the effects typically last for several hours.^{3, 4}

Other short-term effects of heroin can include:^{1, 2, 3, 4}

• Arms and legs feeling heavy.
• Dry mouth.
• Severe itching.
• Nausea and vomiting.
• “Nodding off,” or alternating between a conscious and semiconscious state.
• Warm or flushed skin.
• Slowed breathing and pulse.
• Clouded thinking.

Long-Term Effects of Heroin

Long-term use of heroin can contribute to a variety of health issues that can be persistent, or in some cases, permanent.³ Long-term effects can include:^{1, 3, 4, 5}

• Constipation and stomach issues.
• Increased risk of developing mental health disorders, such as depression.
• Insomnia.
• Lung issues and increased risk of getting pneumonia because of slowed breathing. This risk is greater if heroin is smoked.
• Kidney or liver damage or disease.
• Altered or irregular menstrual cycles in women.
• Sexual dysfunction in males.

Withdrawal Effects of Heroin

Over time, chronic heroin use can cause changes in the brain and in behavior which may lead to addiction.^{2, 3} The brain adjusts to the constant presence of heroin through tolerance and dependence.

With tolerance, increasing amounts of heroin are required over time to get the desired high.^{2, 4} Chronic use can lead to physiological dependence, where the brain and body need heroin to function normally.

When the brain has adapted to a state where it needs heroin to function normally, it’s unable to quickly rebalance and return to normal functioning without heroin. This leads to withdrawal symptoms that are, in many ways, opposite of heroin’s typical effects.⁵

Tolerance and dependence can contribute to developing a heroin addiction, or opioid use disorder. An opioid use disorder is a chronic medical disease characterized by a compulsive need to use heroin or other opioids despite the negative ways it impacts a person’s life.⁴

Withdrawal symptoms typically start about 6-12 hours after the last time heroin was used. Symptoms peak after one to three days, and then gradually improve until they resolve in about a week.^{3, 5} Withdrawal can be extremely uncomfortable and make it difficult to stop using heroin. Common symptoms of heroin withdrawal include: ⁵

• Anxiety.
• Depressed mood and irritability.
• Diarrhea.
• Dilated pupils.
• Difficulty sleeping.
• Excessively tearing eyes or runny nose.
• Fever.
• Goosebumps.
• Nausea and vomiting.
• Aches and pains in the bones and muscles
• Strong cravings for heroin.
• Sweating.
• Yawning.

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Risks of Snorting or Injecting Heroin

There are some specific risks and dangers associated with injecting or snorting heroin. Heroin may be cut with various additives that can cause even more issues.¹ Additionally, sharing or using non-sterile needles, straws, glass tubes, or other paraphernalia can increase the risk of infection or contracting diseases that are spread through bodily fluids like blood, saliva, or mucus.^{1, 4}

Snorting heroin can cause damage or infection of the nasal tissue and perforation of the nasal septum. Some of the common dangers associated with injecting heroin include:^{1, 3, 4, 8}

• Abscesses (swollen, tender, and painful pus-filled infected areas).
• Collapsed and scarred veins, or “track marks.”
• Clogged or blocked blood vessels that can permanently damage the brain, kidneys, liver, and lungs.
• Infections, which can affect the blood vessels, the lining and valves of the heart, or the skin.
• Increased risk of contracting hepatitis C and HIV.
• Increased risk of developing arthritis or other issues because of an immune response to impurities or additives put in heroin.

Risks of Using Heroin While Pregnant

Using heroin during pregnancy poses additional risks to the mother and baby. Babies born to women who used heroin during pregnancy can experience neonatal abstinence syndrome (NAS).³ Since heroin passes through the placenta, the baby also becomes physically dependent, leading to withdrawal symptoms when the baby is born.³

Babies with NAS show symptoms such as:³

• Excessive crying.
• Diarrhea.
• Fever.
• Irritability.
• Slow weight gain.
• Tremors.
• Vomiting.

Treatment involves hospitalizing the baby and providing medication to manage symptoms.³

Heroin withdrawal during pregnancy can lead to miscarriage or preterm birth.⁷ If you are pregnant and addicted to heroin, a doctor can prescribe opioid agonist medications such as methadone or buprenorphine. These are safe and result in better outcomes than continuing to use heroin for both mom and baby.^{3, 7}

Overdose Effects of Heroin

Anyone who uses heroin is at risk of experiencing a life-threatening opioid overdose, which can occur with a single use and cause a person’s breathing to slow down significantly or even stop.¹ An opioid or heroin overdose can have long-lasting effects on the brain, including coma or even death.^{1, 4} Signs of a heroin overdose include:^{2, 4}

• Breathing that is slow, shallow, or stopped.
• Choking or gurgling noises.
• Lips or fingernails that turn bluish.
• Skin that is clammy or cold.
• Vomiting.
• Convulsions.

If a person is showing signs of a heroin overdose, it is important to call 911 immediately.⁴ A heroin overdose can be treated and potentially reversed.⁴ Naloxone (Narcan) is a medication that you or first responders can administer to reverse the effects of heroin or other opioids. The person who overdosed will still require assessment and treatment by a medical professional since additional doses may be needed. The effects of naloxone can wear off before the effects of other opioids such as heroin, causing potentially lethal overdose symptoms to reemerge.^{1, 4}

Treatment for Heroin Addiction

There are various treatment options available for heroin addiction. Effective heroin treatment involves tailoring the treatment plan to meet the individual needs of each person.¹⁰ This may involve a combination of therapies to address substance use and craving, family relationships, mental and physical health issues, legal problems, financial concerns, and employment, as needed.^{10, 11}

Heroin addiction treatment can involve any combination of medical detox, inpatient treatment, outpatient treatment, behavioral therapy, and medication.

Treatment at inpatient and outpatient facilities can provide a range of services, including:^{3, 10}

• Behavioral therapy.
• Medication to manage symptoms of withdrawal and to reduce cravings.
• Treatment for co-occurring medical or mental health conditions.

Inpatient Treatment

Inpatient or residential treatment involves living at a facility for the duration of treatment. Staff is available around the clock and intensive treatment is provided.^{11, 12} Inpatient and residential programs tend to last for about 3-6 weeks although some can last 6 to 12 months.¹⁰

Inpatient treatment can be a particularly good option for people with moderate to severe substance use disorders, have more severe co-occurring mental or physical health disorders, and those without access to safe or stable housing, or have relapsed in less intensive levels of treatment.^{11, 12}

Outpatient Treatment

In outpatient treatment, a person lives at home and attends scheduled appointments at the facility.¹¹ There are different levels of intensity available, ranging from under 9 hours to 20 or more hours of group and individual counseling weekly.¹²

Outpatient treatment is good for people who need to continue working, going to school, attending to personal matters, and those with a good social support system. It gives them the flexibility to continue their recovery without living at a facility 24/7.

Behavioral Therapies for Heroin Addiction

Behavioral therapy can help a person stay motivated towards sobriety, change how they respond to stress or triggers, and improve relationships with family and friends.¹⁰ While there are many forms of behavioral therapy, effective forms of behavioral therapy commonly used for treating heroin addiction include:^{1, 3, 10, 11}

• Cognitive-behavioral therapy (CBT), which helps you identify high-risk situations and develop effective coping skills to prevent relapse.
• Contingency management (CM), which uses small tangible rewards to reinforce desired behaviors, such as attending treatment appointments or providing negative toxicology results.

Medications for Treating Heroin Addiction

Medication is an important part of treating heroin addiction because it can help a person manage withdrawal symptoms, reduce cravings, and may help prevent relapse. It may also reduce the risk of experiencing a potentially fatal overdose.³ Medications used in heroin treatment for opioid use disorder include:³

• Buprenorphine. This is a partial opioid agonist, which means it partially activates opioid receptors in the brain to manage withdrawal symptoms during detox. With a ceiling to its opioid effects, buprenorphine is less likely to result in the rewarding “high” or other adverse side effects associated with heroin or other opioids. Buprenorphine may also be continued beyond the detox phase as maintenance treatment for opioid use disorder.
• Methadone. This is a long-acting full opioid agonist. Methadone completely activates opioid receptors but does it more gradually than other opioids, so there is less chance of a “high” when used during detox. Like buprenorphine, it also helps prevent the onset of opioid withdrawal symptoms. Methadone is only available at specially licensed opioid treatment programs. As with buprenorphine, methadone may also be used as a maintenance treatment for opioid use disorder.
• Naltrexone. This is an opioid antagonist, which means it blocks the effects of opioids, so a person won’t feel the euphoric effects of heroin if they use it. It is used to help a person stay sober and prevent relapse. Naltrexone treatment can start after a person completes the detox phase.

Find Heroin Treatment Centers

If you or a loved one is ready to get help for heroin addiction, call American Addiction Centers at to talk to a caring admissions navigator. We can help you learn about treatment options and check your insurance, so you can start the road to recovery today.

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