The physical effects of heroin start with a rush of pleasure, warm flushed skin, a dry mouth and heavy arms and legs, followed by hours of drowsiness, a slowed heart and slowed breathing. Over months and years, heroin damages the lungs, veins, heart valves and brain and leaves the body dependent on the drug just to feel normal. Any single use can be fatal.
What follows is what heroin does to the body, based on research from the National Institute on Drug Abuse (NIDA), and what recovery can undo.
Short-Term Physical Effects of Heroin
Heroin reaches the brain fast and binds to opioid receptors. People describe a surge of pleasure called a rush. NIDA says it’s usually accompanied by:
- Warm flushing of the skin
- Dry mouth
- A heavy feeling in the arms and legs
- Nausea and vomiting
- Severe itching
After the rush, people are usually drowsy for several hours. Thinking gets cloudy. Heart rate slows. People slip back and forth between awake and half-asleep, which is what “nodding” refers to.
The most dangerous short-term effect is on breathing. Opioids act on the brain stem, which runs automatic functions like breathing and heartbeat. NIDA warns that heroin can slow breathing enough to be life-threatening, and that slowed breathing can lead to coma and permanent brain damage from lack of oxygen.
When Heroin Turns Deadly
Experience doesn’t protect anyone. Street heroin varies in strength from one bag to the next, and NIDA reports that illicit fentanyl is often mixed into heroin or sold as heroin. A dose that felt normal last week can stop someone’s breathing today. Read more in our post on fentanyl abuse symptoms.
Call 911 if someone using heroin can’t be woken, has very slow or stopped breathing, pinpoint pupils, or blue or gray lips. Give naloxone (Narcan) if you have it, and stay with them until help arrives.
Long-Term Physical Effects of Heroin
With repeated use, heroin changes the body in ways that can last long after someone stops. NIDA lists these medical complications of chronic heroin use:
- Insomnia
- Severe constipation
- Lung problems, including several types of pneumonia and tuberculosis, made more likely by poor overall health and heroin’s effect on breathing
- Sexual dysfunction in men
- Irregular menstrual cycles in women
Effects of injecting heroin
Injection adds its own damage. NIDA describes scarred or collapsed veins, abscesses (boils), and bacterial infections of the blood vessels and heart valves, a serious heart infection known as endocarditis. Street heroin often contains additives that don’t dissolve. Those can clog the blood vessels leading to the lungs, liver, kidneys or brain and kill off small patches of tissue in those organs.
Sharing needles or other equipment spreads hepatitis B and C, HIV and other bloodborne viruses. Hepatitis C in particular can quietly damage the liver for years.
Effects of snorting or smoking heroin
Some people believe snorting or smoking heroin is safer than injecting. It avoids needle infections, but it doesn’t avoid overdose, dependence or the other physical effects above. Snorting can also damage the tissue inside the nose. NIDA notes that the routes that reach the brain fastest, injecting and smoking, raise the risk of developing heroin use disorder.
What Heroin Does to the Brain Over Time
The body and brain aren’t separate here. NIDA says repeated heroin use changes the brain’s physical structure, creating imbalances in neuronal and hormonal systems that aren’t easily reversed. Studies have found deterioration in the brain’s white matter, which may affect decision-making, the ability to regulate behavior and how a person responds to stress. Our post on how opioids affect the brain goes further.
Tolerance, Dependence and Withdrawal
Over time, the body needs more heroin to get the same effect. That’s tolerance. Soon it needs heroin just to function, and if use stops or drops suddenly, withdrawal begins. NIDA lists restlessness, muscle and bone pain, insomnia, diarrhea, vomiting and cold flashes with goose bumps. Symptoms usually peak 24 to 48 hours after the last dose and ease after about a week, though some people have lingering symptoms for months.
Heroin withdrawal is rarely deadly by itself, but the relapse that often follows can be. After even a short break, tolerance falls, and a person who goes back to their old amount can overdose. A medically supervised detox makes withdrawal safer and more bearable and opens the door to medications that reduce cravings.
Can the Body Recover From Heroin?
A lot can heal. Sleep, appetite, digestion and energy usually improve in the weeks and months after stopping. Infections can be treated, and hepatitis C is now treatable too. Some damage, like scarred veins, heart valve damage or brain injury from an overdose, may be permanent. The sooner someone stops, the more the body has a chance to repair.
Heroin Addiction Treatment at Covenant Hills
Covenant Hills is a Christian-based treatment center in Orange County, California, with a faith-based heroin addiction program that cares for mind, body and spirit. Clients begin with detox and continue in our residential program, where they can address the pain and patterns that kept them using.
If heroin has taken hold of your life or the life of someone you love, call 800-662-2873 for a free, confidential assessment.
Frequently Asked Questions
What are the physical effects of heroin?
Short term: a rush, warm flushed skin, dry mouth, heavy limbs, nausea, itching, drowsiness and slowed heart rate and breathing. Long term: insomnia, constipation, lung infections, sexual and menstrual problems, and, with injection, collapsed veins, abscesses, heart infections, hepatitis and HIV.
How does heroin kill you?
Usually by slowing or stopping breathing. The brain and body are starved of oxygen, which can cause coma, brain damage or death.
How long does heroin withdrawal last?
NIDA says major symptoms typically peak 24 to 48 hours after the last dose and ease after about a week. Some people have symptoms for months.
Does heroin damage your organs?
It can. Lung infections are common, injection can lead to heart valve infections, and additives in street heroin can block blood vessels to the lungs, liver, kidneys and brain.
