Stimulant drugs
Key facts
- Stimulants are a class of drugs that may make you feel more alert or energetic.
- They work by speeding up your central nervous system.
- Stimulant drugs may make you feel alert, energetic, confident and euphoric.
- Your chance of overdose is much higher when using illegal stimulants, such as cocaine or ice.
- Talk with your doctor if you want to stop taking stimulant drugs but are finding it difficult.
What are stimulants?
Stimulants are a class of drugs that speed up your central nervous system. They may make you feel more alert or energetic. Stimulants include:
- legal drugs, like caffeine and nicotine
- medicines, like methylphenidate (Ritalin)
- illegal drugs, like methamphetamines
Stimulants can come as:
- tablets or capsules
- powders
- small clear crystals
- a white or brown crystal-like powder
These drugs can be:
- chewed
- injected
- smoked
- snorted
- swallowed
Medicines
Some medicines are classed as stimulants. Some examples are listed below:
- caffeine — for mental fatigue and headache
- dexamfetamine, lisdexamfetamine, methylphenidate — for attention deficit hyperactivity disorder (ADHD)
- phentermine — for short-term weight loss
- pseudoephedrine, phenylephrine — when your nose is blocked
- theophylline — for asthma and chronic obstructive pulmonary disease (COPD)
Sometimes medicines aren't used as directed. It may be that they are used:
- to treat a different symptom
- by someone else
- to become intoxicated
This includes both medicines that are:
- prescribed by your doctor
- bought over the counter in a pharmacy or supermarket
This is a type of drug abuse.
Illegal stimulant drugs
Illegal stimulant drugs include:
- amphetamines
- khat (kat or chat)
- methamphetamine, commonly known as ice (crystal meth) or speed
- methylenedioxymethamphetamine (MDMA or ecstasy)
- cocaine
- novel stimulant drugs
Novel stimulant drugs mimic illegal stimulants. These include synthetic cathinones. These drugs are often bought on the internet.
How do stimulants work?
Stimulant drugs speed up the messages travelling between your brain and body.
They can increase your:
- pulse
- breathing rate
- blood pressure
What are the effects of taking stimulants?
Stimulant drugs affect everyone differently. The effects and your chance of harm depend on the type of drug you take.
For example, a cup of coffee (caffeine) won't have the same effects as taking ice or speed. Caffeine also has a much lower chance of harm.
The effects of stimulants also depend on your:
- size, weight and health
- the amount taken
- whether you are used to taking the drug
- whether you take other drugs at the same time
- the environment where you take the drug
Stimulant drugs may make you feel euphoric. You may be more:
- alert
- energetic
- confident
The general effects of low-dose stimulant drugs might include:
- a greater sense of wellbeing
- being talkative
- feeling less hungry
Can stimulant drugs cause long-term problems?
Higher doses of stimulant drugs may cause:
- aggression
- anxiety or paranoia
- headaches
- increased body temperature
- nausea (feeling sick)
- abdominal (tummy) pain
- tremor (shaking)
In some people this can lead to:
Long-term use of stimulant drugs can cause a range of physical and mental health issues.
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
What are the side effects or risks of stimulants?
The side effects caused by stimulant drugs can depend on many things. These include the type of drug you're using.
Stimulant drugs can:
- cause physical harm
- cause mental harm
- damage your relationships
- problems at work
- affect your education
What if I mix stimulants with other drugs?
Mixing stimulants with other drugs can have unpredictable effects and increase your chance of harm.
Ice or speed + antidepressants (MAOIs) — this can cause irregular heartbeat, heart failure and stroke, due to an increase in blood pressure.
Ice + speed or cocaine — this can cause a stroke by putting a greater strain on your heart.
Cocaine or ice or speed + alcohol or opioids or benzodiazepines — this can lead to overdose. This is because your body is under stress dealing with the effects of each drug.
Cocaine + ecstasy — this can increase your chance of having a heart attack. The cocaine also stops some of the desirable effects of ecstasy.
Khat + alcohol — this can cause liver problems.
Reducing harm from taking illicit stimulant drugs
Illicit stimulant drugs can be cut or laced with other substances. There is also no way to know how strong a batch is. This can increase your chance of harm.
Pill testing services can check if a drug is unusually strong or mixed with other substances.
Pill testing services are in some parts of Australia. However, they're not widely available.
Overdose
If you think someone has overdosed on a stimulant, call triple zero (000) for an ambulance. Ambulance officers don't have to call the police.
Your chance of overdose is much higher when using illicit stimulant drugs.
Call an ambulance if someone has any of these symptoms:
- breathing problems
- chest pain
- seizures
- a racing heartbeat
- are very agitated
- are unconscious
You can also overdose using prescribed stimulant drugs.
When should I see my doctor?
Speak with your doctor if you are struggling with substance misuse.
You may find it hard to control how much you use. You may even feel like you need the drug just to get through the day. This can affect your:
- social life
- work and study
- relationships
Your doctor can explain different treatment options, such as:
- counselling and therapy
- support groups
- referral to a doctor who specialises in treating addiction
- inpatient detox and rehabilitation
Your doctor can also prescribe medicines to help you quit smoking or vaping. These are called nicotine replacement therapy (NRT).
They can also help you manage withdrawal symptoms from stimulant drugs.
ASK YOUR DOCTOR — Preparing for an appointment? Use the Question Builder for general tips on what to ask your GP or specialist.
FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.
Resources and support
- To learn more, see the Department of Health and Aged Care website 'What are the effects of taking drugs?'.
- You can find out more about stimulant drugs through the Alcohol and Drug Foundation.
- For free and confidential advice on stimulant drugs, visit the Drug Help website. You can also call the National Alcohol and Other Drug Hotline on 1800 250 015.
- For support quitting smoking, call Quitline or Aboriginal Quitline (staffed by Aboriginal and/or Torres Strait Islander counsellors) on 13 7848.
- The Turning Point website is Australia's leading national addiction treatment, training and research centre. They offer both online and telephone support on 1800 250 015.
- The Touchbase website has drug information for Australians identifying as LGBTIQ+.
- If you want to stop using, call Narcotics Anonymous Australia on 1300 652 820.
- If you are struggling, call Lifeline on 13 11 14. You can also reach out via text on 0477 13 11 14 or chat online.
- Watch a video by NSW Health in English and other languages on getting help when alcohol or drugs are a problem.
You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.
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Last reviewed: April 2025