Cocaine and crack

Cocaine and crack are powerful stimulants and highly addictive. Their effects on your physical and mental health can be serious and sometimes fatal.

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About cocaine and crack


Cocaine is also known as:

  • C
  • rock
  • snow
  • coke
  • blow

It is made from the leaves of the South American coca bush. The leaves are processed into a fine, white powder.
In this form, cocaine can be:

  • sniffed into the nose (snorted)
  • dissolved in water and injected into the vein

The effects of cocaine can be different from:

  • person to person
  • one use to the next

The way cocaine makes people feel depends on many factors, including whether it is:

  • snorted
  • injected
  • smoked


Crack is the form of cocaine you can smoke.

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

Short-term effects of cocaine and crack

Cocaine and crack are fast-acting drugs. Their effects begin within seconds to minutes of use. Cocaine changes brain chemistry so that people feel a sense of well-being (euphoria).

Mental effects

Short-term mental effects can also include:

  • panic
  • anxiety
  • feeling happy and mentally alert
  • having more energy and self-confidence
  • paranoid thinking (believing that people want to harm you)

Physical effects

Cocaine and crack both have moderate and severe physical effects.
Moderate effects can include:

  • dry mouth
  • becoming talkative
  • restlessness and irritability
  • widened (dilated) pupils of the eyes
  • quicker startle reflexes and muscle twitches
  • a heightened sense of sight, sound and touch
  • a temporary decrease in need for food and sleep

More severe effects can include:

  • tremors
  • dizziness
  • violent behaviour
  • nausea and vomiting
  • rapid breathing or difficulty breathing (crack)

Long-term effects of cocaine and crack

Long-term cocaine use may cause a range of physical and mental effects.

Mental effects

The longer people use it, the worse the harm to them can be. Over time cocaine can cause physical changes in the brain. Some of these changes may affect your ability to function in life, at work or at school.
Some ongoing mental health effects linked to long-term use can include:

  • depression
  • sleeping problems
  • extreme changes in mood
  • erratic or violent behaviour
  • feelings of distrust, judgment, jealousy or suspicion (paranoia)
  • losing touch with reality (hallucinations, delusions or psychosis)

Physical effects

Cocaine use can also lead to a variety of long-term physical effects.

Lung, nose and breathing problems

Smoking crack is hard on the lungs. Symptoms of long-term crack use may include:

  • severe chest pain
  • low blood oxygen
  • difficulty breathing, such as:
    • wheezing
    • shortness of breath
    • even breathing failure
  • collapsed or inflamed lungs that fill up with fluid
  • coughing, including coughing up blood from the lungs

People who regularly snort cocaine can develop nose and sinus problems. These include:

  • losing the sense of smell
  • having frequent nosebleeds
  • having a red, chapped or runny nose
  • developing frequent nose and sinus infections
  • developing a hole in the wall between the nostrils

Heart problems

Cocaine stresses the heart, creating high blood pressure and a fast or irregular heartbeat. This increases the possibility of a heart attack. Even young and healthy people are at risk, especially if they use cocaine and alcohol together.

Cocaine use is also linked with an increased risk of stroke.

Stomach problems

Cocaine use is linked to a range of stomach health issues, including:

  • abdominal pain
  • nausea and vomiting
  • changes in appetite
    • ranging between intense hunger to no interest in food, resulting in lack of proper nutrition
  • bowel perforation and decay

Other problems

Prolonged cocaine use may also cause other health issues, such as:

  • impotence
    • males may have difficulty getting an erection
  • low libido
    • cocaine can cause a sharp decline in sex drive in both men and women
  • pregnancy problems
    • if pregnant women use cocaine, they risk
      • stillbirth
      • miscarriage
      • premature delivery
  • bleeding in the brain
    • cocaine can cause blood vessels in the brain to burst, which can be fatal

Risks related to cocaine and crack use

The most serious risk of cocaine or crack use is overdose, which can be lethal. Overdose can include:

  • seizures or convulsions
  • breathing (respiratory) failure
  • stroke (loss of proper blood flow to the brain)
  • irregular heartbeat, heart attack or heart failure

The amount of cocaine needed to cause an overdose varies.

The possibility of accidental overdose is higher when people do not know exactly what drug they are taking or how strong it is. The risk of overdose also increases with the co-use of other substances such as alcohol or opioids, for example. 

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

There are also risks related to how individuals use the drug. If users inject cocaine, they risk complications such as:

  • skin infection
  • blood poisoning
  • infection of the lining of the heart

If you share drug equipment like needles, pipes or spoons, you also risk infection. Contaminated equipment can spread several serious diseases, such as

The substances cocaine is often mixed (cut) with may produce additional adverse or toxic effects.

There is a significant risk of heart problems, even in younger people without pre-existing cardiovascular conditions.

All risks increase if you consumed crack or cocaine in large amounts over a short period, to stay high for hours or days (bingeing).

Substance use disorders and withdrawal

Cocaine and crack are highly addictive. People with a substance use disorder cannot function without their drug. They also need more and more to get the same effect, because their body builds up tolerance.

If you have a substance use disorder related to cocaine or crack you will experience intense cravings. It is difficult to focus on anything else and eventually, your life can be taken over by the urge to get and use cocaine and crack.

If you stop persistent cocaine use abruptly, you will experience withdrawal symptoms, in addition to cravings for cocaine.

Other withdrawal symptoms can include:

  • fatigue
  • irritability
  • depression
  • violent behaviour
  • feeling hungry all the time
  • difficulty sleeping or disturbed sleep
  • loss of physical and mental energy

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