Heroin Addiction

Heroin is a fast-acting opioid, and most of what is sold as heroin now also contains fentanyl, so the strength of any dose is hard to know. This guide covers what heroin does to the body and brain, the physical and behavioral signs of use, the warning signs of an overdose and the naloxone steps that can keep someone alive, and the medications that treat heroin addiction. If someone will not wake and their breathing is slow or shallow, treat it as an overdose: give naloxone and call 911.

What Is Heroin Addiction?

Heroin addiction is a type of opioid use disorder. Someone living with it keeps using heroin even after the drug damages their health, relationships or daily routine. Heroin reaches the brain quickly and binds to opioid receptors, bringing a rush, then hours of drowsiness and slowed breathing. Repeated use brings tolerance, where the same dose no longer has the same effect, and dependence, where stopping brings on withdrawal. Clinicians use the same 11 criteria to diagnose opioid use disorder whether the opioid is heroin or a prescription painkiller.

What is heroin, and what does it look like?

Heroin is an illegal opioid derived from morphine, which the opium poppy produces in its seed pod. The Drug Enforcement Administration (DEA) places it in Schedule I, a group of drugs the agency says have no accepted medical use. It is injected, sniffed, snorted or smoked.

Wound botulism is a further risk for people who inject black tar heroin. Chiva, H, horse, junk, smack, Big H and black tar are among the street names for heroin.

How Heroin Affects the Body and Brain

Heroin acts quickly. Its effects begin within minutes and typically fade within a few hours. People usually describe a rush of pleasure first, and what heroin feels like after that varies, though drowsiness, slower breathing and clouded thinking are common.

The short-term effects are mostly physical, among them:

The larger changes take place in the brain. Heroin binds to opioid receptors throughout the brain and spinal cord, and the relief and pleasure a person feels start there. With repeated use, the reward system that made the drug feel necessary grows less responsive, and the stress system more reactive. Those shifts drive craving and make stopping so difficult. That adaptation, not the high, is most of how heroin affects the brain once use becomes regular.

Signs of Heroin Use and Addiction

Heroin use usually shows in the body before mood changes. Pupils shrink to pinpoints, someone drifts off and then rouses, and breathing slows.

Physical signs

These include small pupils, slowed breathing and drowsiness, abscesses and flu-like withdrawal between doses.

Behavioral signs

Behavior often shifts first.

Opioid use disorder also includes use that continues despite harm, and activities given up.

What you might find

Clinicians also weigh the 11 opioid use disorder criteria.

Long-Term Risks of Heroin Use

Heroin does its damage slowly, and much of it arrives as the physical side effects of heroin, which build over years. These include liver, kidney and lung disease, mental health conditions, and infections that begin at an injection site.

Overdose is the most immediate danger, and the risk has climbed as fentanyl and other drugs have found their way into what people buy.

Heroin, Fentanyl and Xylazine

Most of the heroin available in the United States now carries illegally made fentanyl, a synthetic opioid that can be as much as 50 times more potent than heroin. People often cannot tell whether what they are using includes it. Some supplies also carry xylazine, an animal sedative that people sometimes call “tranq.”

Xylazine is not an opioid, so naloxone will not reverse the sedation it causes. Even so, give naloxone whenever an overdose is suspected, because xylazine is usually mixed with opioids. Xylazine is also tied to wounds that can become infected, and that can turn dangerous when they go untreated. Fentanyl test strips can indicate whether a drug holds fentanyl, though they may miss stronger substances such as carfentanil.

Heroin Overdose: Signs and What to Do

A heroin overdose slows a person’s breathing, and can stop it. The signs include pinpoint pupils, a person who will not wake, breathing that is slow or shallow, a body that has gone limp, lips or nails that look discolored, and choking or gurgling sounds.

Naloxone reverses an opioid overdose, so give it and call 911. The order:

1. Give naloxone if you have it on hand, and call 911.
2. Keep the person awake and breathing if you can.
3. Turn them onto their side so they are less likely to choke.
4. Stay with the person until emergency help arrives.
5. If they are still not breathing normally 2 to 3 minutes after that dose, give another one.

Naloxone will not hurt a person who is not overdosing on an opioid, and a pharmacy sells it without a prescription. Every state and Washington, D.C. has an overdose Good Samaritan law, and those laws give a person who calls 911 some legal protection.

Heroin Withdrawal

Withdrawal timing is fairly predictable: symptoms begin about 12 hours after the last dose, the worst stretch runs 1 to 3 days, and it eases within 7 to 10 days. Withdrawal is the body adjusting after regular use stops, and it feels like a severe flu that will not let up for days. On its own it is rarely life-threatening, though dehydration from vomiting and diarrhea needs care.

The symptoms usually arrive in a recognizable pattern:

The riskiest stretch comes after the worst has passed, not during it. Tolerance drops quickly once heroin clears the body, so a return to the dose someone used before, especially heroin cut with fentanyl, can bring on an overdose. Most opioid overdose deaths occur in people who have just detoxed.

The hours and days follow a fairly predictable opioid withdrawal timeline, and medical detox adds supervision through the roughest stretch for anyone who needs it.

Heroin Addiction Treatment Options

Heroin addiction is treated with one of the FDA-approved medications for opioid use disorder, usually alongside counseling and support. Methadone and buprenorphine lower the risk of death after an overdose, and either can begin without detox coming first. Settings range from an opioid treatment program and a doctor’s office to telehealth and residential care.

Many people take medication and see a counselor as outpatients. Others need inpatient rehab for structure and a safer place to stay, or begin with medical detox and go straight into continuing care, since detox is a first stage rather than treatment on its own. Insurance and Medicaid often pay, and Medicaid must cover every FDA-approved medication for opioid use disorder, so it helps to check how to pay for rehab before intake.

How to Help Someone Who Uses Heroin

Begin with what keeps a person alive tonight. Keep naloxone, the medicine that reverses an opioid overdose, where anyone in the household can reach it, and learn the overdose signs above. Then pick a calm moment when the person is sober, say what you have noticed, without blame, and name one step you can take together: a doctor’s appointment, or calling the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357, which is free, confidential and open 24/7.

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Six steps cover most of it:

1. Carry naloxone and know the overdose steps above.
2. Say what you have seen while the person is sober.
3. Keep the language respectful and person-first, and skip ultimatums.
4. Point to one route forward: a doctor’s appointment, FindTreatment.gov, or the SAMHSA National Helpline.
5. Look after yourself too; family support groups are for the people who worry.
6. If someone is in crisis, 988 takes calls and texts, and 911 is for a medical emergency.

Nobody can force another person to accept help. Staying steady and keeping the door open can make saying yes easier, and helping a loved one with addiction covers more of it.

Frequently Asked Questions About Heroin Addiction