The latest National Drug Strategy Household Survey has found Australians are using cocaine much more than a decade ago.
The 2019 survey found that the proportion of Australians who have recently used cocaine in the past 12 months is 4.2%. That’s a 70% increase from 2016 when it was just 2.5%, and more than 200% on 2001 when it was 1.3%.
Use has increased in all adult age groups in the survey. The proportion of men in their 20s who had recently used almost doubled from 7.3% to 14.4%.
When a drug spikes in usage, it’s natural for the public to be worried about the individual and social harms that may result.
Our recent experience with an uptick in weekly and daily usage of crystal methamphetamine (‘ice’) saw a notable increase in hospitalisations and people seeking treatment for dependence.
Should we be equally worried about an increase in cocaine related harms?
What is cocaine?
Cocaine is the psychoactive part of the coca plant. It has similar effects to methamphetamine but the effects are not as long lasting.
Some of the immediate effects of cocaine include:
- feelings of euphoria, exhilaration and confidence
- accelerated heart rate
- increase in body temperature
- a burst of energy
- dilated pupils
- loss of appetite
- the urge to have sex
It produces these effects by enhancing the activity of dopamine in the brain, a neurotransmitter associated with ‘rewarding’ life-enhancing behaviour such as eating food or having sex.
The most common type of cocaine used in Australia is cocaine hydrochloride, which is a white powder that is usually sniffed through the nose (‘snorted’), or sometimes injected. There are other types of cocaine, like ‘crack’, the crystal version which is usually smoked. But it isn’t commonly available in Australia.
Health risks
Health risks associated with cocaine use can be divided into three categories: risks associated with intoxication, risks associated with long-term use and risk of dependence (‘addiction’).
Intoxication
Although many people use cocaine without any negative effects, there are some unpleasant, harmful and even lethal effects of cocaine intoxication. Some of these negative effects include:
- Feelings of restlessness, excitability, sleeplessness, loss of libido, nervousness and aggression.
- Symptoms of psychosis including paranoia, hallucinations and delusional thoughts.
- Abdominal pain and nausea.
- Adverse cardiovascular events including disturbances in heart rhythm and heart attack.
- Cocaine-induced excited delirium, experienced by vulnerable users resulting in hyperthermia (high body temperature), extreme behavioural agitation and, in some cases, violent behaviour.
- Cocaine overdose, including abnormally fast heart rhythms, high blood pressure and increased risk of cardiovascular events.
Cocaine-related fatalities are most commonly due to cardiac arrest and seizures, especially when other drugs are used at the same time.
Combining cocaine and alcohol increases the risk of cardiac arrest because the two substances interact to produce cocaethylene, a substance which is directly harmful to the heart.
Mixing the stimulant cocaine and the depressant heroin (sometimes called a ‘speedball’) is particularly dangerous because the effects of one can mask the as the body struggles to handle simultaneous depressant and stimulant effects.
Cocaine in Australia has been known to have been cut with harmful chemicals such as levamisole (anti-worm medication), which can harm a person’s immune system and cause skin lesions.
Longer-term harms
Heart problems are a well-documented side effect of long-term cocaine use. These include atherosclerosis (the build-up of fatty plaque on artery walls) and damage to the heart muscle impairing its function. Cocaine-related heart problems increase a person’s lifetime risk of heart attacks, heart failure and cardiac-related death.
Regular cocaine use has also been associated with a number of abnormalities in the the blood vessels around the brain. This increases a person’s risk of stroke and cerebral haemorrhage (bleeding within the brain).
Smoking crack cocaine can cause lung damage, and injecting it is associated with increased risk of blood borne virus infection.
Regularly snorting cocaine may lead to damage to the inner lining of your nose resulting in inflammation in the mucous membrane of the nose (chronic rhinitis), reduced sense of smell, nosebleeds and septal perforation, where a hole develops in the wall between the nasal passages.
Dependence
Around 6% of people who use cocaine will become dependent on it. Dependence occurs when your body gets used to having cocaine. People who are dependent can experience withdrawal symptoms when they stop using.
Symptoms of cocaine withdrawal can include:
- Irritability and anxiety
- Decreased appetite
- Poor concentration and exhaustion
- An intense desire to use
Treatment for cocaine dependence is effective and most people do recover from alcohol and other drug dependence.
Reducing the risk
Steps can be taken to reduce the risk of short-term and long-term harms from cocaine use. Some common tips to reduce harms include:
- Avoid using cocaine with alcohol and other drugs
- Use small amounts, less often, to reduce the risk of developing dependence
- Never use alone
- Avoid ‘binging’, cocaine has a half-life of 2-4 hours and the greatest risk of overdose is from using again within this time period
- Test drugs for adulterants
- Snort water before and after to protect your nasal mucosa from damage
- If injecting, always use sterile equipment and avoid sharing to reduce the risk of blood borne virus infection
How similar are cocaine and ice?
At first glance there are many parallels between cocaine and ice, both drugs:
- Are stimulants
- Carry a risk of psychotic symptoms
- Carry a risk of cardiovascular problems
- Are habit forming
However, there are also important differences.
Ice is much longer lasting than cocaine, with 50% of cocaine metabolised within 1 hour of consumption compared to 12 hours for ice. The prolonged stimulant effects of ice can have particularly deleterious effects on people who use, particularly when sleep is impacted.
Moreover ice, unlike cocaine, does more than merely inhibit the re-uptake of dopamine – it actively stimulates dopamine release, which can be toxic to brain neurons due to heavy long-term use.
There are also important differences in purity and patterns of usage within the Australian context.
The switch amongst people who use methamphetamine in Australia to high purity ice or crystal methamphetamine as opposed to ‘speed’ or base forms of the drug was strongly correlated with resulting harms. In contrast, the purity of cocaine in Australia has increased only slightly over the last decade and remains relatively steady.
In 2008–09, the annual median purity of cocaine samples seized by police ranged between 9.5 per cent and 64.5 per cent between States and Territories. In 2017–18. the annual median purity ranged from 42.1 per cent to 62.0 per cent.
Amongst people who regularly use drugs, the perceived purity of cocaine has remained stable.
Finally, whilst the proportion of people who use cocaine weekly has increased from 2.8% in 2010 to 4.5% in 2019, this remains a small percentage of users, with most (57.2%) people who use cocaine doing so only once or twice a year.
This is contrast with methamphetamine, with 16.9% of people who use surveyed in 2019 using once a week or more. Increased frequency of drug use is strongly correlated with drug-related harms and dependence.
Overall, both the effects of cocaine and the way people are using cocaine in Australia make it less likely to generate the population level harms observed for ice.