Nervous system | Better Health Channel

Stimulants are a class of drugs that speed up your central nervous system. They may make you feel more alert or energetic. Stimulants include:
Stimulants can come as:
These drugs can be:
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:
This includes both medicines that are:
This is a type of drug abuse.
Illegal stimulant drugs include:
Novel stimulant drugs mimic illegal stimulants. These include synthetic cathinones. These drugs are often bought on the internet.
Stimulant drugs speed up the messages travelling between your brain and body.
They can increase your:
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:
Stimulant drugs may make you feel euphoric. You may be more:
The general effects of low-dose stimulant drugs might include:
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.
The side effects caused by stimulant drugs can depend on many things. These include the type of drug you're using.
Stimulant drugs can:
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.
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.
Your chance of overdose is much higher when using illicit stimulant drugs.
Call an ambulance if someone has any of these symptoms:
You can also overdose using prescribed stimulant drugs.
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:
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.
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: May 2025










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