Friendly Print preview

... see also ADF sheet

Cannabis (marijuana)

What is cannabis?

Cannabis is a drug that comes from a plant called Cannabis sativa or the Indian hemp plant. It contains a chemical called tetrahydrocannabinol, which makes people get 'high'. It is commonly called marijuana, grass, pot, dope, hash or hashish. Other slang terms are Acapulco Gold, ganga, herb, J, jay, hay, joint, reefer, weed, locoweed, smoke, tea, stick, Mary Jane and Panama Red. Marijuana comes from the leaves, while hashish is the concentrated form of the resinous substances from the head of the female plant and can be very strong (it comes as a resin or oil ).

Is cannabis a new drug?

No. It is a very old drug and was used by the Chinese about 5000 years ago.

What are the effects of taking cannabis?

This depends on how much is taken, how it is taken, how often, whether it is used with other drugs and on the particular person. The effects vary from person to person.

Effects of a small to moderate amount

• feeling of well-being and relaxation
• decreased inhibitions
• woozy, floating feeling
• lethargy and sleepiness
• talkativeness and laughing a lot
• red nose, gritty eyes and dry mouth
• unusual perception of sounds and colour
• nausea and dizziness
• loss of concentration
• looking 'spaced out' or drunk
• lack of co-ordination

The effects of smoking marijuana take up to 20 minutes and usually last 2-3 hours, then drowsiness follows.

The main problem is habitual use with the development of dependence, although dependence (addiction) is not very common.

What happens with dependence and long-term use?

The influence of 'pot' has a severe effect on the personality and drive of the person. They lose their energy, initiative and enterprise. They become bored, inert, apathetic and careless. A serious effect of smoking pot is the loss of memory.

Some serious problems include:

• crime
• lack of morality-scant respect for others and their property
• respiratory disease (more potent than nicotine for lung disease)
• often a prelude to taking hard drugs
• becoming psychotic (resembling schizophrenia)

What about driving under the influence?

Cannabis affects co-ordination and perception, and so it is dangerous to drive a car or ride a motorbike after using it. In an experiment, several people were given 'pot' to smoke and then asked to drive around a test circuit. Most made a mess of their driving, including crashing into posts and retaining walls. It is particularly dangerous when mixed with alcohol. Other activities such as surfing, waterskiing and motorbike riding are also dangerous.

What is the management?

The best treatment is prevention. People should either not use it or limit it to experimentation. If it is used, people should be prepared to 'sleep it off and not drive.

Copyright 1995: John Murtagh, Professor of General Practice
Monash University, Melbourne, Australia