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10 February, 2010

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Cannabis (marijuana)

Cannabis, or marijuana, is the most commonly used illegal drug. It comes from the Cannabis sativa plant. It can be smoked or eaten and comes in a variety of forms such as dried plant leaves and flowers (‘heads’), a crumbly light brown or dark brown resinous material called ‘hash’, or in the form of a very strong oil called ‘hash oil’.

Cannabis comes in different forms
There are a variety of different forms of cannabis:

Marijuana – is the most common and least powerful form of cannabis. It is made from dried plant leaves and flowers. The flowers, or ‘heads’, are the most potent forms of the plant. Marijuana resembles chopped grass and ranges in colour from grey-green to greenish-brown. It is usually smoked in a waterpipe (bong), a pipe or in a hand-rolled cigarette (joint).
Hashish – consists of small blocks of dried cannabis resin. Blocks range in colour from light brown to nearly black. The concentration of THC (delta-9 tetrahydrocannabinol) in hashish is higher than in marijuana.
Hash oil – is a thick, oily liquid extracted from hashish and ranges in colour from golden-brown to black. It is usually spread on the tip or paper of cigarettes and then smoked. Hash oil is more powerful than the other forms of cannabis.

A chemical provides the ‘high’
The psychoactive chemical in cannabis that makes users feel ‘high’ is called THC (delta-9 tetrahydrocannabinol).

Cannabis is a depressant drug
Depressant drugs do not necessarily make you feel depressed. Rather, they slow down the central nervous system and the messages going to and from the brain to the body.

Cannabis effects vary from person to person
The effects of cannabis are different for each person. The effect can vary according to the mood or atmosphere in which it is used. The immediate effects of cannabis can last approximately two to three hours and may include:

A feeling of relaxation and sense of wellbeing
Reduced concentration
Decreased coordination
Distorted perceptions of time, space and distance
Increased heart rate
Drowsiness
Increased appetite
Increased talkativeness
Reddened eyes
Impaired driving ability.

Larger doses or stronger forms of cannabis can exacerbate these effects and result in other effects such as:

Confusion
Restlessness
Feelings of excitement
Hallucinations
Anxiety or panic
Detachment from reality
Paranoia
Nausea.

Long-term users may experience additional effects
Cannabis may also have additional effects on long-term users, including:

The risk of asthma, emphysema, shortness of breath, chest infections, and throat, mouth and lung cancers
Poor concentration, memory loss and learning difficulties
Depression of the immune system, which increases the risk of developing infections
Serious mental illness, such as schizophrenia.

Cancer-causing (carcinogenic) substances
Cannabis smoke has more tar and contains a higher concentration of certain cancer-causing (carcinogenic) agents than the smoke from tobacco.

Cannabis can cause psychosis
Research suggests that cannabis use can make existing psychotic symptoms worse. It may even bring on symptoms in people who are predisposed to psychosis if they have a personal or family history of the disorder.

It is also believed that cannabis use, especially if heavy and regular, may cause an individual to experience psychotic symptoms that can last for a few days. These episodes are often characterised by visual or aural (hearing-related) hallucinations.

Tolerance and dependence
A tolerance to cannabis can develop with regular use, which means the person has to take increasing quantities to get the same effect. Some people can become psychologically and/or physically dependent on cannabis.

How to prevent the negative health effects of cannabis
The best way to avoid the harmful effects of cannabis is to avoid its use, especially for people who have experienced a psychotic episode in the past or who have a family history of psychosis.

Where to get help

DirectLine Tel. 1800 888 236 – for 24-hour confidential drug and alcohol telephone counselling, information and referral
DrugInfo Clearinghouse, Australian Drug Foundation Tel. 1300 858 584 – for information http://druginfo.adf.org.au/
Your doctor
Hospital emergency departments
Drug and alcohol treatment centres
Community health centres
Family Drug Help – for information and support for people concerned about a relative or friend using drugs Tel. 1300 660 068

Things to remember

Cannabis has many harmful effects on health.
Cannabis is an illegal drug.
Cannabis impairs the user’s driving ability.
Avoid cannabis if you have had a psychotic episode or there is a history of psychosis in your family.
Help is available 24 hours a day, seven days a week.

You might also be interested in:
Birth defects - drugs and medications.
Cannabis and psychosis.
Drugs - some facts.
Teenage health.

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