Heroin facts Block of heroin with injecting equipment. © Australian Drug Foundation, 2011

What is heroin?

Effects of heroin

Tolerance and dependence

Getting help

Heroin use in Australia

What is heroin?

Heroin is made from the opium poppy.

It is one of a group of drugs known as “opioids”. Other opioids include opium, morphine, codeine, pethidine, oxycodone, buprenorphine and methadone. Heroin is made from the opium poppy.

Heroin and other opioids are depressant drugs. Depressant drugs do not necessarily make you feel depressed. Rather, they slow down the activity of the central nervous system and messages going between the brain and the body.

Alcohol, benzodiazepines, GHB and cannabis are also depressant drugs.

Other names

Heroin is also known as "smack", "skag", "dope", "H", "junk", "hammer", "slow", "gear", "harry", "big harry", "horse", "black tar", "china white", "Chinese H", "white dynamite", "dragon", "elephant", "homebake" or "poison".

What does it look like?

Heroin can range from a fine white powder to off-white granules or pieces of brown "rock". It has a bitter taste but no smell, and is generally packaged in "foils" (aluminium foil) or small, coloured balloons.

How is it used?

Heroin is most commonly injected into a vein. It is also smoked ("chasing the dragon") or added to cannabis or tobacco cigarettes, or snorted.

Effects of heroin

The effects of any drug (including heroin) vary from person to person. How heroin affects a person depends on many things including their size, weight and health, also whether the person is used to taking it and whether other drugs are taken around the same time.

The effects of any drug also depend on the amount taken. This can be very hard to judge as the quality and strength of illicit drugs can vary greatly from one batch to another.

There is no safe level of drug use. Use of any drug always carries some risk—even medications can produce unwanted side effects. It is important to be careful when taking any type of drug.

Immediate effects

Depending on how heroin is taken, the effects may be felt within 7-8 seconds (injecting) or within 10–15 minutes (snorting or smoking). The effects of heroin can last for approximately 3–5 hours.

Low to moderate doses

Some of the effects that may be experienced after taking heroin include:

  • feelings of intense pleasure
  • strong feelings of wellbeing
  • confusion
  • lowered cough reflex
  • pain relief
  • reduced sexual urges
  • drowsiness
  • slurred and slow speech
  • reduced coordination
  • constricted pupils
  • dry mouth
  • slow breathing rate
  • decreased heart rate and blood pressure
  • nausea and vomiting
  • reduced appetite.

Higher doses

A high dose of heroin can cause a person to overdose. This means that a person has taken more heroin than their body can cope with.

The risk of overdose increases if the strength or purity of the heroin is not known. Injecting heroin increases the risk of overdose due to large amounts of the drug entering the blood stream and quickly travelling to the brain.

High doses of heroin can intensify some of the effects. People may also experience:

  • impaired concentration
  • going "on the nod" (falling asleep)
  • shallow and slow breathing
  • nausea and vomiting
  • increased sweating and itching
  • urge to pass urine but difficulty doing so
  • drop in body temperature
  • irregular heartbeat
  • unconsciousness
  • death.

Naloxone (also known as Narcan®) reverses the effects of heroin, particularly in the case of an overdose. Naloxone can be administered by authorised medical personnel such as ambulance officers.

After an overdose, it is strongly advisable to seek assessment at a hospital or by a medical practitioner.

Coming down

A person who is coming down from using heroin may feel irritable as the drug leaves their body. They may also feel depressed when coming down.

Long-term effects

The long-term effects of heroin use on health can include:

  • dependence
  • constipation
  • menstrual irregularity and infertility in women
  • loss of sex drive in men
  • intense sadness
  • cognitive impairment
  • tetanus
  • damage to heart, lungs, liver and brain.

Some other long-term effects of heroin are related to the method of use:

  • Repeated snorting damages the nasal lining.
  • Frequent injecting in the same place can cause inflammation, abscesses, vein damage and scarring.
  • Injecting can also result in skin, heart and lung infections.
  • The impurities and additives in heroin, if injected can also damage veins. This can also cause thrombosis.

Other effects of heroin use

Taking heroin with other drugs

The effects of mixing heroin with other drugs, including alcohol, prescription medications and over-the-counter medicines, are often unpredictable.

Mixing heroin with other depressant drugs (such as alcohol or benzodiazepines) increases the depressive effects and can result in an increased risk of respiratory depression, coma and death.

Combining heroin with stimulant drugs such as amphetamine also places the body under great stress.

Pregnancy and breastfeeding

Most drugs that a mother takes will cross the placenta and affect her foetus, or will be present in her breast milk.

Using heroin while pregnant can increase the chances of problems in pregnancy such as miscarriage, or going into labour early, which can mean that babies are born below birth weight.

Heroin is often "cut" with other substances that can also cause problems during pregnancy and affect the developing foetus.

Read more about the effects of taking heroin during pregnancy or breastfeeding.

Check with your doctor or other health professional if you are using or planning to use heroin or any other drugs during pregnancy or while breastfeeding.


It is dangerous to drive after using heroin. The effects of heroin, such as drowsiness and reduced coordination, can affect driving ability. The symptoms of coming down and withdrawal can also affect a person's ability to drive safely.

Read more about the effects of heroin on driving.

Heroin and the workplace

Under occupational health and safety legislation, all employees have a responsibility to make sure they look after their own and their co-workers' safety. The effects of heroin such as drowsiness and confusion can affect a person's ability to work safely and effectively.

The symptoms of coming down and withdrawal can also affect a person's ability to work safely and effectively.

Preventing and reducing harms

Sharing needles, syringes and other injecting equipment can greatly increase the risk of contracting blood borne viruses such as hepatitis B, hepatitis C and HIV (human immunodeficiency virus—the virus that causes AIDS).

The alcohol and drug service in your state or territory can provide information on where to obtain clean needles and syringes.

Tolerance and dependence

There is evidence that after prolonged use heroin is highly addictive. People who use heroin regularly can develop dependence and tolerance to it, which means they need to take larger amounts of heroin to get the same effect.

Dependence on heroin can be psychological, physical, or both. People who are dependent on heroin find that using the drug becomes far more important than other activities in their life. They crave the drug and find it very difficult to stop using it.

People who are psychologically dependent on heroin may find they feel an urge to use it when they are in specific surroundings or socialising with friends.

Physical dependence occurs when a person's body adapts to heroin and gets used to functioning with the heroin present.


If a dependent person stops taking heroin, or severely cuts down the amount they use, they will experience withdrawal symptoms because their body has to get used to functioning without heroin.

Symptoms can start within 6 to 24 hours after the last dose. Heroin withdrawal symptoms usually peak within 1 to 3 days and gradually subside in 5 to 7 days.
Some of the withdrawal symptoms that may be experienced include:

  • cravings for heroin
  • restlessness
  • yawning
  • increased irritability
  • depression
  • crying
  • diarrhoea
  • low blood pressure
  • stomach and leg cramps, muscle spasms
  • vomiting
  • goose bumps
  • runny nose
  • insomnia
  • loss of appetite
  • elevated heart rate.

Getting help


In Australia, there are many different types of treatments for drug problems. Some aim to help people to stop using a drug, while others aim to reduce the risks and harm related to drug use.

Find out more about treatment.

What to do if you are concerned about someone's heroin use

If you are concerned about someone's drug use, there is help available. Contact the alcohol and drug information service in your state or territory.

What to do in a crisis

Always call triple zero (000) if a heroin overdose is known or suspected—and remember that paramedics are not obliged to involve the police.

If someone overdoses or has an adverse reaction while using heroin, it is very important that they receive professional help as soon as possible. A quick response can save their life.

Visit the Better Health Channel to read St John Ambulance's advice on drug overdose.

Heroin use in Australia

According to the National Drug Strategy Household Survey, in 2010, 1.4 per cent of the Australian population aged 14 years and older had used heroin at some stage in their lifetime

For more statistics about the use of heroin in Australia, visit our Quick statistics page.

Heroin and the law

Heroin is illegal in Australia.

Federal and state laws provide penalties for possessing, using, making, selling or driving under the influence of heroin.

Read more about heroin and Australian law.

Please note: This information does not constitute legal advice and should not be relied upon in this way. The information is correct at the time of publication. For information specific to your situation contact a legal aid service in your state or territory.

National drug policy

Australia's national drug policy is based on harm minimisation. Strategies to minimise harm include encouraging people to avoid using a drug through to helping people to reduce the risk of harm if they do use a drug. It aims to reduce all types of drug-related harm to both the individual and the community.