Opioid overdose

Anyone using prescribed or street opioids can have an overdose. Opioids affect the part of your brain that controls your breathing. When you take more opioids than your body can handle (overdose), your breathing slows. It can cause death in a worse case event.

Opioid overdose is an emergency and must be treated immediately. Call 111 for help if you suspect someone has overdosed on opioids.

On this page, you can find the following information:

What are opioids?

Opioids are medicines commonly used to treat pain. Examples of opioids include codeine, morphine, oxycodone, methadone, fentanyl, tramadol and buprenorphine. Opioids can also be so-called street drugs, such as heroin.

Who is at risk of an opioid overdose?

Anyone using prescribed or street opioids can have an overdose, but there are some things that put you at higher risk.

You are at risk of an opioid overdose if you are taking prescription opioids more often or at higher doses than recommended, or if you are taking opioids with alcohol or other medicines such as benzodiazepines (sleeping tablets).

An overdose can also happen if you misuse opioids. For example, extended-release opioid tablets are meant to be swallowed whole. If you crush or break these pills before taking them, it may cause an overdose because too much of the drug is released at once.

Injecting drugs and using drugs of unknown purity or strength can also increase your risk of opioid overdose. Opioids that are available on the street are of unknown strength and type and so their effects can vary. 

Having other health conditions, like liver or kidney disease or breathing problems, increases your risk of opioid overdose. 

What are the symptoms of an opioid overdose?

A person may have opioid overdose if they:

  • are very sleepy or hard to wake up (passed out)
  • have irregular, little or no breathing 
  • are snoring unusually or deeply
  • are making gurgling sounds
  • have blue lips or nails
  • limp and floppy
  • vomit
  • have tiny pupils.

It can cause death in a worst case event.

Image credit: Opioid overdose family support toolkit Ohio State University, US

How is opioid overdose treated?

Opioid overdose is an emergency. Call 111 for help if you suspect someone has overdosed on opioids.

While you are waiting for help:

  1. Stay with the person.
  2. Check for danger.
  3. Try to wake the person.
  4. Make sure airways are clear. Tilt the head back and clear the airways.
  5. Stay on the phone with the emergency services. They can provide advice until help arrives. They may ask you to provide rescue breathing or CPR.

Naloxone emergency kit

Opioid overdose is treated with the medicine naloxone. If taken soon enough after an opioid overdose, it can reverse the effects of opioids and save lives. If you are at risk of opioid overdose you can be prescribed a naloxone emergency kit for use in an emergency. If you have access to naloxone read about how to administer naloxone in an emergency.

How can I prevent opioid overdose?

Reduce the risk

If you use opioids, you can reduce your risk of overdose or death by:

  • not using when you are by yourself
  • knowing your tolerance (how much you can take)
  • having a naloxone kit available, and knowing how to use it
  • using a small amount of an opioid first to check the strength
  • not taking opioids with alcohol or other drugs (unless prescribed by your doctor).
If you are taking opioids for pain

‘Start low, go slow’

If you have been prescribed an opioid start on a low dose and increase slowly as your doctor has prescribed it. Do not exceed the prescribed dose. Different formulations (eg, tablet, capsule, patch) will suit different people. Do not take someone else's opioid medicine.

Set a goal

Set a goal for treatment. It should not just be about pain reduction but also a focus on returning back to activities such as exercise or work.

When to reduce or stop taking opioids

Have an agreement in place in advance on when to start reducing or stopping an opioid. This is known as tapering.

The main reason for tapering is that the longer an opioid taken, the more likely you are to:

  • feel worse
  • find that it doesn’t work as well
  • put yourself at greater risk of harm.

Harm can include developing a dependence (physical, psychological or both), opioid-induced hyperalgesia, and tolerance or withdrawal.

Read more about lowering opioid doses. 

Regular reviews

See your GP regularly. They can help monitor the progress of treatment. If the benefits of taking opioids are outweighed by the potential harm, there are other options for treatments. These include non-opioid medicines and non-medicine treatments such as physiotherapy and acupuncture. Read more about non-medicine treatments for pain.

Did you know that you can report a side effect to a medicine to CARM (Centre for Adverse Reactions Monitoring)? Report a side effect to a product

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Credits: Maya Patel, Pharmacist, Auckland. Reviewed By: Sandra Ponen, Pharmacist Last reviewed: 08 Feb 2022