What is a drug overdose?

An overdose occurs when you take more of a drug than your body can handle. It can also happen when you take the wrong drug or mix different drugs. This can cause serious harm or be fatal.

A drug overdose can be accidental or intentional (on purpose).

A drug is any substance that changes how your body or mind works. This includes legal, illegal and illicit substances.

• Legal drugs include alcohol, caffeine and nicotine. There are laws that set who can take these drugs based on your age and location. Regulations control their content, such as the amount of alcohol and nicotine, and how they are sold.
• Illegal drugs include party drugs such as cannabis, speed, cocaine and MDMA. These drugs are not regulated. This means their strength and ingredients are unpredictable.
• Illicit drugs include illegal drugs and substances like glue or paint thinner used improperly. It also includes prescription medicines, such as opioids or sleeping pills, got or used illegally.

Prescription medicines are another form of legal drugs. They can also cause an overdose if you take them incorrectly, either accidentally or intentionally.

What are the symptoms of drug overdose?

Symptoms of an overdose can be hard to predict. This is because you often don’t know what's in illegal drugs, or how strong they are.

A drug overdose can be dangerous and, in some cases, fatal. The most common illicit drugs overdoses include:

• opioids — such as heroin and oxycodone
• amphetamines — such as speed and ice
• MDMA — also known as ecstasy

Overdoses can happen with any drug. Generally, drugs that cause overdose can be classified as either stimulants or depressants. Understanding these 2 types will help you recognise their effects and potential harm.

Stimulant drug overdose

Stimulant drugs speed up the messages travelling between your brain and body. Examples include speed, ice, cocaine and MDMA.

Symptoms of a stimulant drug overdose may include:

• irritability or restlessness
• paranoia or anxiety
• severe stomach pain
• difficulty breathing
• seizures (uncontrolled movements)
• stroke
• coma

The person may also experience severe chest pain, which can indicate a heart attack. Their heart may stop beating.

Call triple zero (000) immediately and ask for an ambulance if your or someone else’s chest pain is severe, getting worse or has lasted for 10 minutes.

Depressant drug overdose

Depressant drugs slow down the messages travelling between your brain and body. Examples include heroin, oxycodone, codeine and fentanyl.

Symptoms of a depressant drug overdose may include:

• vomiting
• muscle weakness
• pale or clammy face
• slow or irregular heartbeat
• breathing that is shallow, irregular, or not happening at all
• choking sounds or a gurgling noise

The person may be awake but unable to respond, or they may lose consciousness.

If you are with someone who is unable to respond or is unconscious, call triple zero (000) for an ambulance. If the person stops breathing, start CPR.

When should I call an ambulance or go to the emergency department?

Call for an ambulance immediately if you think someone has taken an overdose or someone shows symptoms of a drug overdose. The person doesn’t need to have all the symptoms to be overdosing.

Don't worry about getting in trouble (or getting someone else in trouble) for using illegal drugs. Paramedics don’t need to involve the police unless they feel in danger. They are focused on saving lives.

What should I do while waiting for the ambulance?

While waiting for the ambulance:

• Follow any advice given to you by the 000 call operator.
• Make sure the person has enough air. Open windows and loosen tight clothing.
• If the person isn’t responding, don’t assume they’re sleeping. Roll them onto their side and tilt their head back. Start CPR if they stop breathing.
• Try to find out what drug was taken, how much, when, and if the person has any medical conditions.
• Don’t make the person vomit, and don’t give them food or drink.
• Don’t leave the person alone.

What causes drug overdose?

An overdose can be intentional or accidental. An intentional overdose is when a person takes drugs on purpose to harm themselves. An accidental overdose can occur for several reasons, including the following:

• taking unknown substances — with illegal drugs it's hard to know what's in them or how strong they are
• having impaired judgement — drugs can affect your memory, thinking and judgment. You may not think of the risks of taking more or mixing different drugs.
• someone spiking your drink — this means a person adds alcohol or another drug to your drink without your knowledge
• having different reactions — everyone’s body reacts differently to drugs. A drug that is safe for one person may be dangerous for another.

How is a drug overdose diagnosed?

When someone has a suspected drug overdose, a doctor will do tests and ask questions about what they took to diagnose them.

Test may include:

• blood tests — to identify the substances in the person's body
• electrocardiogram (ECG) — to check the heart's activity to see if it’s affected by drugs

How is a drug overdose treated?

Most drug overdoses are treated in hospitals. Your doctor (GP) may also help diagnose and manage substance abuse.

In the hospital, you may receive:

• intravenous fluids (IV) — to improve low blood pressure.
• antidotes — to counteract the toxic effects of some drugs. For example, naloxone can reverse the effects of heroin and other opioids.
• activated charcoal — so the body absorbs less of the drug. It works only for certain drugs and if given within an hour of taking the drug.

A mental health professional can also provide treatment in some situations, for example, if the overdose was a suicide attempt. If the overdose was related to addiction, a referral to a drug and alcohol service may help.

What are the complications of a drug overdose?

A drug overdose usually doesn’t cause long-term harm, and most people recover fully. However, it can sometimes lead to serious complications such as:

• permanent organ damage — this can happen to organs such as the liver and kidneys
• brain damage — if an overdose causes someone to stop breathing, it can reduce oxygen to the brain
• death — some overdoses can severely damage organs and result in death

Can drug overdoses be prevented?

Preventing drug overdoses is important for staying safe and healthy.

Here are some tips to help avoid a drug overdose:

• Avoid party drugs to reduce your risk of overdose.
• Know what you're taking. If you take party drugs, it can be hard to know what's in them or how strong they are.
• Prevent mixing. If you take party drugs, do not mix them with other drugs or alcohol.
• Watch your drink to prevent it from being spiked. If someone you don’t know well offers you a drink, go to the bar with them.
• Know your limits. Remember that everyone's body reacts differently to drugs.
• Seek support if you experience mental health or drug issues. Ask your doctor about support systems in your area.

Resources and support

If you, or someone you know, is having suicidal thoughts and is in immediate danger, call triple zero (000). To talk to someone now, call Suicide Call Back Service 1300 659 467 or Lifeline on 13 11 14.

The National Alcohol and Other Drug hotline provides free and confidential advice about alcohol and other drugs. Call 1800 250 015.

The Alcohol and Drug Foundation has information on drugs, and provides support for people affected by alcohol or other drugs.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available 24 hours a day, 7 days a week.

Other languages

The below resources are available in several languages:

• Fentanyl drug facts
• Opioid Overdose Response - Nyxoid nasal spray
• Opioid Overdose Response - Prenoxad naloxone injection
• Opioid Overdose Response - Naloxone ampoule injection

Aboriginal and/or Torres Strait Islander people

The Australian Indigenous Health Info Net offers resources to reduce harmful alcohol and other drug use in Aboriginal and/or Torres Strait Islander communities. They offer information on subjects such as:

• illicit drugs
• opioids, amphetamines and cocaine
• kava