Frequently Asked Questions

Cannabis is difficult to classify pharmacologically because it has a variety of effects. It is primarily a depressant drug, however, it can have hallucinogenic and some stimulant properties. Marijuana, hashish and hashish oil come from the cannabis plant.

Cannabis can also been known as mull, pot, dope, weed, leaf, gunja, marijuana, grass, smoke, green, hashish or hashish oil, amongst other street names.

Cannabis is usually smoked in hand-rolled cigarettes (joints) or water pipes (bongs). The drug is quickly absorbed into the bloodstream through the walls of the lungs. Intoxication is felt when the drug reaches the brain which can take a few minutes and may last for up to 5 hours. When cannabis is eaten, the absorption of the drug is much slower, taking up to 3 hours to enter the bloodstream and the amount of food in the stomach and the user (e.g. weight, gender and other drugs used) will determine how quickly a person feels the effects.

Cannabis is primarily a depressant drug, which means it decreases alertness by slowing down the activity of the central nervous system. However, it can also have hallucinogenic (can alter perception and can cause hallucinations, such as seeing or hearing something that is not there) and some stimulant (increases the body's state of arousal by increasing the activity of the brain) properties.

The effects of cannabis can change from person to person as with any drug. This is because the effects of drugs change with person to person depending on the persons characteristics (such as physical size, gender, mood, diet, fitness, age, expectations and health), the drug itself (such as the amount used and its purity), and how it is taken and the environment a person is in when using the drug.

Short term effects of cannabis on your body can include loss of concentration, impaired balance and reduced coordination, increased heart rate, reddened eyes and increased appetite. Cannabis intoxication can also cause confusion, restlessness, a detachment from reality, hallucinations, anxiety and panic attacks.

Cannabis use can also cause problems later in life, not just while using the drug. There is a growing body of research that indicates cannabis causes significant harm to the community, particularly in relation to physical and mental health, and wellbeing. Long term effects of cannabis can include respiratory disorders (bronchitis, asthma and emphysema), risk of cancer (especially lung cancer), decreased concentration, memory and learning abilities and interference with sex drive and hormone production. Cannabis use can increase the risk of mental health problems, especially in young people. This risk increases the earlier a person starts and the more they use.

Frequent use of cannabis can affect the brain by decreasing the user's ability to concentrate and remember things and can also impact on learning ability. Research indicates that cannabis affects the frontal cortex of the brain, leading to less self-control.

Cannabis use can increase the risk of mental health problems, especially in young people. This risk increases with frequency and amount of cannabis use. The frequent or even occasional use of cannabis can cause anxiety, depression, paranoia and psychosis in those people who have a vulnerability to mental health problems. People who use cannabis in their teens may also have an increased risk of developing schizophrenia. This risk also increases with frequency and amount of cannabis use.

Dependency is a complex issue. Some drugs are more physically addictive while others are mentally or socially addictive.

It has been suggested that cannabis use can lead to dependency. Research indicates that 1 in 10 people who try cannabis become dependent, with young people more at risk of dependence following cannabis use than older people.

Cannabis can be detected in saliva for 6-12 hours after use. It is suggested that a single joint can last from 2 to 25 days until it is no longer detectable in urine, and 12-36 hours until it is no longer detectable in blood. However, heavy cannabis use can be detected for longer in urine.

It is important to note that the detection of drugs and their metabolites in any biological sample (saliva, urine and blood) can change depending on the individual person and their biological factors and most suggested time frames are based on scientific studies, but individual results may vary.

There is no safe level of cannabis use. Because cannabis is harmful, it is against the law for people in Western Australia to use, possess, cultivate or sell / supply cannabis, or to possess pipes and other smoking implements containing detectable traces of cannabis.

It is important to note that the detection of drugs and their metabolites in any biological sample (blood, urine and saliva) can change depending on the individual person and their biological factors and most suggested time frames are based on scientific studies but individual results may vary.

It is against the law to sell cannabis smoking paraphernalia (e.g. bongs) or to display them for sale in a shop or retail outlet. Selling cannabis smoking paraphernalia to a child under the age of 18 years attracts a higher penalty than selling to an adult.

A person convicted of a drug offence will receive a criminal record and this can lead to difficulties in getting a job, credit or visas for overseas travel.

Using cannabis can also impact on your life in many ways. For example, the cost of purchasing cannabis can lead to financial problems and drug use can lead to social and emotional problems that affect relationships with family and friends.

We would recommend that you contact WA Police for any other questions on cannabis and the law (www.police.wa.gov.au).

Under the CIR scheme, police may issue a CIR notice to eligible people found in possession or use of small amounts of cannabis, and/or possession of a smoking implement containing traces of cannabis.

However, a person found in possession of a small amount of cannabis may still be charged with the more serious offence of possession of cannabis with intent to sell or supply, if police have relevant evidence.

The CIR scheme does not apply to offences involving the possession or cultivation of cannabis plants, or possession of any quantities of cannabis resin (hash), hash oil, or other cannabis derivatives. These offences will be prosecuted through the courts.

A person who has been given a CIR will be required to book and complete a Cannabis Intervention Session (CIS) within 28 days or elect to have the matter heard in court.

Police have the discretion whether or not to issue a CIR to an eligible person. A person is eligible for a CIR if they are aged 14 years or over, and is found using, or in possession, of not more than 10 grams of cannabis, and/or found in possession of a smoking implement containing detectable traces of cannabis.

An adult can only receive one CIR while a young person (aged 14-17 years) can be given a CIR on two separate occasions.

An adult who previously received a CIR, and commits a second or subsequent minor cannabis related offence, will be prosecuted through the courts.  A young person who commits a third or subsequent minor cannabis related offence however, will be referred to a Juvenile Justice Team where appropriate under the Young Offenders Act 1994, rather than being charged.

If a person had previously been convicted of a minor cannabis related offence and was an adult at the time of conviction, he or she would be ineligible to receive a CIR. Previous convictions for serious drug offences and offences of a violent and/or sexual nature may also preclude a person from being given a CIR.

The options are:

• book and complete a Cannabis Intervention Session (CIS) within 28 days after being given the CIR; or
• apply in writing to have the matter heard and determined in court.

If you are unable to complete a CIS within the 28 day period, you may apply in writing to police for an extension of time, however these are only issued in extenuating circumstances. 

If you book and complete a CIS you will not be required to appear in court. No further action will be taken against you for the alleged offence and you will not receive a criminal conviction.

If the 28 day period has expired and you have not completed a CIS or elected to have the matter heard and determined in court you will be prosecuted through the courts or, if you are a young person, the matter may be referred to a Juvenile Justice Team.

If cannabis is used in pregnancy the baby may be born smaller and lighter than other babies. Low birth weight can be associated with infections and breathing problems.

Little is known about the effects of cannabis smoking on breastfeeding. It is believed that some of the drug will pass through breast milk to the baby, with risks to the child.

It is recommended that women discuss their drug use with their doctor (or other health professional) if they are planning a pregnancy, currently pregnant or breastfeeding, including prescribed and over-the-counter medicines.

Cannabis use can increase the risk of mental health problems, especially in young people. This risk increases with frequency and amount of cannabis use. The frequent or even occasional use of cannabis can cause anxiety, depression, paranoia and psychosis in those people who have a vulnerability to mental health problems. People who use cannabis in their teens may also have an increased risk of developing schizophrenia. This risk also increases with frequency and amount of cannabis use.