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Stimulant drugs

10-minute read

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:

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:

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:

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:

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:

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

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.

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: April 2025


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