Heroin is made from morphine, a substance that comes from the opium poppy. It is highly addictive. The withdrawal symptoms can be painful. An overdose can be fatal.

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About heroin

Like all opioids, heroin is a depressant that slows down the activity of the nervous system. It is also known as:

  • H
  • junk
  • skag
  • dope
  • dust
  • horse
  • smack
  • China White

Pure heroin is a fine, white, bitter-tasting powder. Illegal heroin is often mixed with other things that look the same, including:

  • sugars
  • starch
  • quinine (a drug made from cinchona bark)

Heroin is increasingly found laced with fentanyl, a more powerful, synthetic opioid.

Illegal heroin may vary in:

  • purity
  • colour
  • consistency

It may look like a:

  • white powder
  • dark sticky gum
  • brown grainy substance

Heroin is consumed in different ways. The powder may be:

  • sniffed up the nose (snorting)
  • smoked (chasing the dragon)
  • dissolved in water
    • injected into a vein (mainlining)
    • injected into a muscle or under the skin (skin-popping)

Heroin is controlled under Schedule I of the Controlled Drugs and Substances Act. Activities such as sale, possession and production are illegal, unless authorized for medical, scientific or industrial purposes.

Short-term effects of heroin

How quickly heroin affects you depends on how you take it.

When you inject heroin into a vein, it reaches your brain and produces a rush of well-being (euphoria) within seconds. The effects last anywhere from 45 seconds to a few minutes.

Smoking or snorting produce effects just as quickly, but they are less intense.

When you inject heroin into a muscle or under the skin the effects occur more slowly, usually within 20 minutes.

After the quick ‘rush’ of well-being a period of calm follows. This may last up to about an hour. Other short-term effects may last for about 3 to 5 hours.

To avoid symptoms of withdrawal, people who use heroin may feel the need to use it every 6 to 12 hours.

Mental effects

Other short-term mental effects include:

  • dizziness
  • confusion
  • going “on the nod” (being in and out of consciousness)

Physical effects

Short-term physical effects include:

  • drowsiness
  • feeling heavy in the arms and legs
  • nausea and vomiting
  • smaller (constricted) pupils
  • severe itching or warm/hot sensation on the skin
  • slowed breathing
  • headaches

Long-term effects of heroin

With long-term use, heroin has many harmful effects on your body and mind. The more you use heroin, the more your health is affected.

Mental effects

Long-term heroin use can cause:

  • difficulty in controlling impulsive behaviour
  • substance use disorder
  • lack of emotion (apathy)
  • unstable mood
  • depression, suicidal thoughts
  • learning and memory problems

Physical effects

Many long-term physical effects are due to using non-sterile needles and syringes. Sharing drug equipment can lead to:

Other physical effects include:

  • constipation
  • poor nutrition, weight loss
  • sexual problems in men
  • irregular menstrual cycles in women
  • irregular heartbeat, cardiac arrest
  • insomnia

Using heroin during pregnancy can harm your unborn child. It is associated with:

  • low birth weight
  • premature delivery
  • high infant mortality

Risks related to heroin use

Heroin use carries a great risk of overdose. Users rarely know the actual strength of the drug they are taking.

Heroin takes effect very quickly, especially when injected.  If you take too much you may lose consciousness almost immediately.

Symptoms of overdose include:

  • unresponsiveness
  • slow, shallow breathing
  • gurgling sounds or snoring
  • cold, clammy or bluish skin
  • severe sleepiness or loss of consciousness

In large enough quantities heroin can stop your breathing. This can be fatal.

Overdose is more likely if you take heroin with other depressant drugs, such as:

Combining drugs can increase each drug's effects. This puts you at an increased risk.

In cases of overdose, naloxone can block the depressant effects.  It must be given within 20 to 30 minutes after the heroin has been taken.

Staying at the scene of an overdose is important to help save the life of the person overdosing. The Good Samaritan Drug Overdose Act gives some legal protection for individuals who witness an overdose and call 911 or their local emergency number for help.

Substance use disorders and withdrawal

Physical dependence on heroin and substance use disorder can develop within weeks of regular use. The need to get heroin can take over a person’s life.

How severe withdrawal symptoms from heroin are depends on your health and the:

  • amount and frequency of use
  • length of time you’ve used the drug
  • conditions under which withdrawal happens

Symptoms of withdrawal can start 6 to 12 hours after the last dose. They may reach their peak between 24 and 72 hours and subside greatly after about 5 to 7 days.

Individuals will often inject heroin to avoid withdrawal symptoms.

In addition to intense cravings for the drug, during the withdrawal period you may experience:

  • insomnia
  • a racing heartbeat
  • abdominal cramping
  • involuntary muscle spasms
  • nausea, vomiting and diarrhea
  • anxiety, restlessness and depression
  • sweating or cold flashes with goosebumps (also known as "cold turkey")

Heroin withdrawal is rarely fatal for adults.

You can treat a substance use disorder involving heroin with opioid substitution medications, such as buprenorphine or methadone. These work by stimulating the same brain receptors as heroin. This treatment can:

  • prevent heroin withdrawal
  • reduce or eliminate the cravings

About 20 to 30% of patients treated for opioid use disorder achieve long-term abstinence.

Problematic heroin use may affect a person’s life. Opioid use disorders are associated with:

  • crime
  • poverty
  • family dysfunction

Mortality most often results from overdose, accidents or infections.

Heroin will reach the placenta if you are pregnant while using it. Newborns may have withdrawal symptoms, including:

  • sweating
  • irritability
  • trouble feeding
  • excessive crying
  • shaky or jerky movements
  • having diarrhea and a need to vomit

A baby with severe heroin withdrawal can develop seizures and die.

Babies undergoing withdrawal need to be treated in a hospital.

Therapeutic uses

Prescription heroin (diacetylmorphine) may be obtained through the Urgent Public Health Need process. This is for treating problematic opioid use under medical supervision.

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