Cocaine and crack

Cocaine and crack are powerful stimulants and highly addictive. Their effects on people's physical and mental health can be serious and sometimes fatal. Learn about what cocaine and crack are, and how they affect the mind and body.

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About cocaine and crack

Learn about cocaine and crack, what they are made of and how they are used.


Cocaine (also known as C, rock, snow, coke and blow) 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 veins

The effects of cocaine can be different from person to person, and also from one use to the next. The way cocaine makes people feel depends on many factors, including whether it is:

  • sniffed
  • injected
  • smoked


Crack (also known as rock and freebase) is the smokable form of cocaine.

To make crack, the cocaine powder is melted and compressed into rocks, which can then be smoked. Crack reaches the brain faster. In higher doses, it is also more addictive than regular cocaine that is snorted.

Short-term effects of cocaine and crack

Cocaine changes brain chemistry so that people feel a sense of pleasure (euphoria).

Mental effects

Short-term mental effects can include:

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

Physical effects

Cocaine and crack use have both moderate and severe physical effects.

Moderate effects can include:

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

More severe effects can include:

  • nausea and vomiting
  • tremors
  • dizziness
  • faster heart rate and higher blood pressure
  • rapid breathing or difficulty breathing (crack)
  • violent behaviour
  • heart problems
  • substance use disorder
  • overdose


Because crack produces a very short-lived effect, people who smoke the drug often use it several times. Some consume large amounts over a short period of time or stay high for hours or days (bingeing).

People who use cocaine also want to avoid the drop in mood (crashing) that happens after the drug wears off. When they crash, people may feel:

  • anxious
  • tired
  • hungry
  • depressed
  • suicidal

As a result, individuals may take even more cocaine to deal with the crash.


The most serious short-term side effect of cocaine or crack is the possibility of an overdose, which can be lethal.

Some of the more negative effects associated with overdose can include:

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

The amount of cocaine needed to cause an overdose varies. It can happen to individuals who take a lot of the drug or only a little. The possibility of accidental overdose is higher when people:

  • do not know exactly what drug they are taking or how strong it is
  • use other drugs along with cocaine (such as alcohol)
  • use the drug in a way that gets it into their system more quickly (for example, snorting)

Remember that if you or someone else is in need of medical help, you do not need to be afraid of police involvement. Saving a life is the number one priority for emergency responders. Canada’s Good Samaritan Drug Overdose Act protects individuals who seek help for an overdose from charges and conditions related to the possession of drugs.

Long-term effects of cocaine and crack

Long-term cocaine use may cause a range of physical symptoms. The drug can harm the body in different mental and physical ways.

Mental effects

Using cocaine affects the mind in a number of ways. The longer people use it, the worse the harm can become. Over time, cocaine can also cause physical changes in the brain. Some of these changes may affect an individuals' ability to function in their lives, at work or at school.

Some ongoing mental health effects linked to long-term use can include:

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

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 may include:

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

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

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

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.

Stomach problems

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

  • nausea and vomiting
  • changes in appetite
    • these changes range between intense hunger and no interest in food, resulting in a lack of proper nutrition
  • abdominal pain

Other problems

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

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

If individuals inject cocaine, they risk complications such as:

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

If individuals share drug equipment like needles, pipes or spoons, they also risk infection. Several serious diseases can be spread by contaminated equipment, such as:

Substance use disorders and withdrawal

Cocaine and crack are highly addictive. People with a substance use disorder cannot function without it, and need more and more to get the same effect. This is known as tolerance.

A person with a substance use disorder related to cocaine or crack experiences intense cravings. It is difficult to focus on anything else and eventually, their lives can be taken over by the urge to get and use cocaine and crack.

If persistent cocaine use is stopped abruptly, people experience withdrawal symptoms, including cravings for cocaine.

Other withdrawal symptoms can include:

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