Last partial update: July 2016 - Please read disclaimer before proceeding
Classification of illicit substances
Drugs that act on the brain (psychoactive drugs) can be classified into two broad groups; those that stimulate brain activity and those that depress it. The commonly used drugs in each group appear in the table below.
Stimulant drugs tend to make people more alert and excited and have effects on the body such as raising pulse rate and body temperature. These effects are exaggerated in stronger drugs or when an overdose is taken, and this can lead to anxiety, agitation, hallucinations, aggression, and psychotic episodes. (A psychotic episode occurs when the person losses touch with reality. As might be expected, hallucinations commonly occur as part of these episodes.)
Depressant drugs are the most commonly used group and tend to slow down the brain, giving a calm relaxed feeling. When these are taken to excess they can slow the brain down so much that the person goes into a coma and eventually stops breathing. (This is the cause of deaths that occasionally occur with a heroine overdose.)
Types of drug commonly used in Australia (Listed in approximate decreasing order of use in Australia) |
|
Stimulants |
Depressants |
Caffeine |
Alcohol |
Nicotine |
Cannabis / marijuana |
Amphetamines |
Heroine |
Ecstasy |
GBH (‘Fantasy’) |
Methamphetamine (‘Ice’) |
Ketamine |
Cocaine |
|
LSD |
|
Nervous system depressants
Alcohol See separate section on ‘Alcohol Abuse'
Cannabis / marijuana
What is cannabis? The main psychoactive compound in cannabis is delta-9-tetrahydrolcannabinol (THC), although the plant contains many other psychoactive compounds in smaller quantities. It is a central nervous system (brain) depressant that is usually smoked, although it also can be eaten when added to cakes or biscuits. Cannabis generally makes people slow down and feel sleepy and its effects can last up to 12 hours.
Is cannabis getting stronger? There has been much talk in the media about the increasing strength of the cannabis available now compared to 20 years ago. In actual fact there has not been a great change in the concentration of drug in the plant itself and in many places the drug potency has not changed. What has happened in places where the THC levels have risen in cannabis, such as in the USA, the Netherlands and to some extent Australia, is that more of the available cannabis is being sourced from the buds or head parts of the plant and this has a higher concentration of THC. In the USA the level of THC in cannabis has increased from 1% to 4%.) In the end, as with most illicit drugs, there is a significant variation in the concentration of active ingredient contained in cannabis available in Australia, which means its effect is unpredictable and people have to try it to see what effect it has; and this can be an unpleasant and sometimes dangerous process.
How common is cannabis use? It is widely used in Australia, with approximately 33 per cent of Australians over 14 having tried the drug at some time. A common but very misguided reason for trying it in preference to other drugs is that it is natural (not man made like ‘Ecstasy’) and thus less harmful. The average age at first use is about 19 years and users are most likely to be in their twenties. Overall, Australia has the highest cannabis use of all OECD countries.
At present about 18 per cent of teenagers use cannabis, which is significantly less than the number using the drug a few years ago. The reason for this is that cannabis is no longer a ‘cool’ drug in this age group. Males are more likely to use the drug and more likely to use more of it when they do. The most reliable predictor of cannabis use in teenagers is heavy alcohol use in early teens.
Harm from cannabis use Most people using cannabis (up to 90%) are infrequent users and do not experience short or long term harm from the drug. Most teenagers are aware of this fact, which is one reason why they feel they can initially try the drug to see what it is like. Also, using cannabis does not mean that other illicit drugs will be used, as many teenagers decide to ‘draw the line’ at cannabis use. For example, about 2% of adult Australians have used heroin at some time compared to 33% with cannabis.)
However, dependence does develop in about 10 per cent of users. These people are usually very frequent users and are at risk of long-term harm from their use. While earlier use in teenagers is associated with an increased risk of harm from use, generally speaking there is no way of knowing who will end up in this 10% group when they start using cannabis; and this uncertainty is often quite scary for prospective teenager users.
There have been no reported deaths from the direct effects of cannabis. The most significant problems are associated with mental illness.
Acute or short term effects last about four to six hours and include hilarity, altered perception of colour and music, palpitations, increased appetite and dry mouth. More serious effects that occur with heavy use include an increase in psychotic symptoms such as delusions, especially if a pre-existing psychotic illness in present. (Cannabis can precipitate a schizophrenic episode in people with this condition.) Thinking ability and memory are impaired, and problems with coordination affect the ability to drive, operate machinery etc, especially if alcohol is used at the same time. Decreased inhibitions can lead to increased risk taking behaviours, such as dangerous driving and unsafe sex. Some people can become anxious when taking cannabis and paranoid thoughts are common. Simultaneous use of other drugs can worsen these effects. Physical effects include red eyes, hunger and dry mouth.
Chronic, long term effects include impaired thinking and motivation, impaired emotional responsiveness, reduced educational achievement and chronic bronchitis / emphysaema. Depression is also more common and can occur in adolescent users. Use of cannabis in young adolescence increases the risk of other illicit drug use and smoking cigarettes and is also associated with poor school performance. Chronic use can cause reduced fertility in both males and females
Mental illness and cannabis Pre-existing mental illnesses are often made worse by cannabis use, especially in people with psychoses (mostly schizophrenia) and depression / anxiety disorders. Cannabis use can also be associated with the first episode of mental illness. (In such cases it is probably unmasking a predisposition to the illness that may or may not have otherwise occurred later in life.) These effects are particularly marked in adolescents. Cannabis use is common amongst people admitted to psychiatric hospitals. People with pre-existing psychiatric illness are more likely to become dependent on cannabis and should be discouraged from using the drug, as should those with a strong family history of mental illness, especially schizophrenia.ß
About 10 per cent of chronic cannabis users develop physical dependence (i.e. symptoms of tolerance and withdrawal) and many more develop a psychological dependence on the drug; that is, it becomes part of their lives and they find it difficult to cease use. All people with signs of dependence should be encouraged to reduce or cease their use. Withdrawal in dependent people can last from days to a few weeks and is associated with anxiety, depression, irritability, lethargy, vivid dreams, night sweats, cravings and insomnia. Withdrawal is best achieved through counselling, although a short course of benzodiazepine sedatives or antidepressant drugs may be useful. Information about quitting can be gained from state and territory Alcohol and Drug Information Services. Also a National Cannabis Information and Prevention Centre has recently been founded in Australia. (See the further information section at the end of this section.)
Reducing harm from cannabis
- People with pre-existing psychiatric illness should be discouraged from using the drug, especially those with schizophrenia and anxiety / depression.
- The drug should not be used when pregnant.
- The drug should not be used in people with epilepsy.
- Use under the age of 16 should be avoided as its effects are very unpredictable.
- Driving, operating machinery etc should not be performed when using the drug. (Cannabis stays in the blood for a long time and people who have a blood test for cannabis may still be positive several days after using the drug.)
- Use with other drugs such as alcohol should be avoided as the effects of the drug increase.
- Regular use should be avoided to avoid the risk of addiction.
- Cannabis possession and use is illegal throughout Australia and the legal consequences of use and possession can be severe, including fines, and even gaol and a life-long criminal conviction in some circumstances.
- Smoking any drug causes harm to the lung if it is done for a long period, either by bongs or joints. (While bongs may filter out some toxic chemicals, they also filter out the active chemical THC and the user thus needs to take more of the drug to gain the same effect.) Eating cannabis significantly delays its effect.
Heroin
Heroin is a narcotic derived from the poppy plant. It acts as a central nervous system (brain) depressant and is mostly administered through injection, although it can also be smoked. It is hard to estimate heroin use but it was thought that there were about 60,000 (and perhaps up to 120,000) Australians using this drug in 1997. Dependence occurs in somewhere between 25 and 50 per cent of users, which means that at least half those using the drug are occasional, recreational users.
There are both short and long term problems with heroin use. Short term problems include vomiting, constipation, tiredness and, most significantly, shallow (depressed) breathing. With overdosage, breathing can stop altogether, resulting in death. Long term side problems include a greater likelihood that overdosage will occur, an increased likelihood of contracting serious viral infections (HIV and hepatitis B and C), vein damage, skin infections, constipation and pneumonia. There are also significant social problems surrounding heroin dependence, including illegal behaviour to finance heroin purchases.
Outcomes for heroin dependent people
Most dependent people are between the age of 20 and 40. About a third of heroin dependent people are able to quit, another third continue to use intermittently, and a final third continue severe dependence behaviours, are put in goal, or die.
There are various treatments for heroin dependence, the main ones being supervised withdrawal and methadone. Treatment is best conducted by a specialised drug rehabilitation unit.
Reducing harm from heroin use
Harm prevention is of paramount importance in assisting people using heroin. The main aim should be to minimise the risk of death due to overdose and infection with HIV and hepatitis B and C.
Safe injecting procedures
Strategies include the following.
- Choose a safe place to inject and NEVER inject alone
- Cleanliness to reduce infection. This includes washing hands well before commencing, cleaning the area where drug mixing is to be done before and after use, and cleaning the injection site before and after drug use.
- Never share needles or any other materials used for mixing or administering heroin.
- Use needles and syringes only once.
- Recap the needle after use.
- NEVER recap another person’s needle
- Dispose of contaminated materials in a safe manner that will not endanger others.
Heroin is usually mixed with other compounds and varies in strength. To avoid overdosage, people should buy heroin from a regular, trusted dealer. If the person is using heroin from a new supplier or is a new user or is starting use again after even a short break, he or she is at increased risk of overdose and should use a small amount first to test the strength. Never use heroin at the same time as other drugs, especially other depressant drugs such as alcohol, cannabis or tranquillisers, as this increases the risk of overdose.
Heroin use in pregnancy
Heroin use can affect the baby both while in the uterus and after birth via breast milk and should be avoided where possible during pregnancy. Problems include an increased incidence of foetal deaths, stillbirths, infections such as hepatitis B and C and HIV, and sudden infant death syndrome.
How to help a person who has overdosed on heroin
The signs of overdosage include very slow breathing, cold skin, a slow heart beat, muscle twitching, blue tips of fingers, slowness to respond or unresponsiveness, and a gurgling sound in the throat. The following can help.
- Phoning the ambulance immediately
- Staying with the person and trying to keep them awake by talking to them
- Putting them on the floor on their side if the person looks like they’re about to lose consciousness
- If the person is unconscious-
- Putt them on their side in the recovery position.
- Assess their breathing, clear their airway, and do mouth-to-mouth resuscitation if needed
They should never be placed in the shower to ‘wake up’, injected with anything else (unless by a health professional), or have anything placed in their mouth.
Other depressant (sedative) party drugs - Ketamine and GHB (Fantasy)
Ketamine
Ketamine is a veterinary anaesthetic drug whose effects resemble those of alcohol at toxic doses. Other effects include disordered thoughts and bizarre actions.
GBH (also called ‘Fantasy’)
GBH is an anaesthetic drug with sedative properties. Overdose is quite common and dangerous as it can cause vomiting, coma, convulsions and death. This is more likely if alcohol, also a depressant drug, is taken at the same time. Treatment in intensive care is usually required. Unfortunately it is a very cheap drug. It has a history of use in ‘drink spiking’ / 'date rape'. (See section on teenage alcohol use for information on drink spiking and date ape.)
Further reading
Teenagers, Alcohol and Drugs What your kids really want and need to know about alcohol and drugs. by Paul Dillon. Published by Allen & Unwin, 2009.
Further information
Alcohol and Drug Information Service in your state.
This service will provide information and/or advice regarding problems. They can also refer callers to health professionals that can help them personally regarding alcohol and other drug problems.
ACT Ph 6205 4545; NSW Ph 9361 8000 or 1800 422 599: NT 8981 8030 or 1800422 599; Qld Ph 3236 2414 or 1800 177 833; SA Ph 1300 131 340; Tas 1800 811 994; Vic Ph 9416 1818 or 1800 136 385; WA Ph 9442 5000 or 1800 198 024) Check directory assistance if these numbers have changed.
Australian Drug Information Network www.adin.com.au
Information about alcohol, tobacco and other drugs.
Australian Drug Foundation www.adf.org.au.
Another good general site regarding drug use; easy to access information about most types of drugs.
Family Drug Support 24 hour hotline www.fds.org.au
Ph 1300 368 186 (throughout Australia)
National Health and Medical research Council National Guidelines on Responsible Drinking https://www.nhmrc.gov.au/health-topics/alcohol-guidelines
National Cannabis Information and Prevention Centre https://ncpic.org.au
Brief Intervention: the Drink-less package (University of Sydney) http://sydney.edu.au/medicine/addiction/drinkless/index.php
This site the very helpful and commonly used alcohol reduction program ‘Drink-less’. It can be downloaded free or orders can be taken from the site.
Information for doctors
Specialist advice for doctors regarding drug and alcohol problems (24 hour service)
NSW: Drug and Alcohol Specialist Advisory Service: Ph: 1800 023 687 or (02) 9361 8006
Vic, Tas, NT: Drug and Alcohol Specialist Advisory Service. Ph: 1800 812 804 or (03) 9416 1818
ACT: Alcohol and Drug Program. Ph: (02) 6205 4545
WA: Dept of Health Clinical Advisory Service. Ph 1800 688 847 or (08) 9442 5042
Qld: Alcohol and Drug Information Service. Ph: (07) 3636 7098 or (07) 363607599