What is an opioid?

An opioid is a substance that blocks pain messages between the brain and the rest of the body. This can give you pain relief, but may also slow your heart rate and breathing.

Most opioids, such as morphine and codeine, can be used to treat pain, while others such as methadone can also be used to treat addiction and manage withdrawal symptoms. Opioids are prescribed for the short-term treatment of moderately severe or severe pain, such as pain experienced following surgery or an injury. They also help people manage pain caused by cancer and terminal diseases.

There are 2 groups of opioids: those that occur naturally and come from the opium poppy are called opiates — for example codeine, morphine and heroin — and those that are created synthetically, such as pethidine and fentanyl.

How do I know if my medicine is an opioid?

If you have been prescribed a pain relief medicine, ask your doctor or pharmacist if it is an opioid. This is important, since prescription opioids can cause serious side effects even when used exactly as prescribed by your doctor.

Opioids used to treat pain include:

• buprenorphine
• codeine
• fentanyl
• hydromorphone
• methadone
• morphine
• oxycodone
• tapentadol
• tramadol

Are prescription opioids effective for chronic pain?

Evidence shows that opioid medicines are not very useful for managing chronic non-cancer pain — sometimes called persistent pain. A person is considered to have chronic pain if they experience constant daily pain lasting 3 months or more over 6 months.

Opioids can be effective treatments for the short-term management of acute pain — for example, after a recent injury or surgery — and for people with cancer pain or who are receiving palliative care.

Evidence shows that the longer a person takes an opioid, the less pain relief they will receive. This is because the body gets used to the dose of opioid that's being taken — known as ‘tolerance’. When a person develops tolerance to an opioid medicines, they need higher doses of the medicine to produce the same effect. But higher doses increase the risk of serious side effects.

Long-term use of opioids can also make a person more sensitive to pain — this is known as ‘opioid-induced hyperalgesia’.

There are different ways to manage chronic non-cancer pain, including medications such as antidepressants or paracetamol, and non-medicine treatments, including:

• physiotherapy or hydrotherapy with a health professional who understands your needs
• practising a relaxation therapy such as mindfulness or yoga
• attending a group pain management program
• changing your diet with support from a dietitian
• stopping smoking
• speaking to a counsellor, including on the phone or using video call
• taking daily walks or following an exercise plan

Talk to your doctor about which treatments may work best for you.

Do prescription opioids have side effects?

Prescription opioids can have side effects even if you use them exactly as your doctor recommends, including life-threatening breathing problems — the risk is higher:

• when you first start taking opioids
• after a dosage increase
• if you are older
• if you have an existing lung problem

Other common side effects are:

• nausea and vomiting
• drowsiness
• constipation
• loss of appetite
• dizziness
• itchiness
• dry mouth
• confusion and slurred speech
• slow and shallow breathing

These side effects may make it difficult or unsafe for you to drive or operate heavy machinery. If you have recently started taking an opioid medication or changed the dosage, you may be at higher risk of having an accident.

Opioid medicines can also have some serious long-term side effects, including:

• becoming tolerant to the medicine — needing higher doses to get the same result, which can result in a lethal overdose
• becoming dependent on opioids — experiencing withdrawal symptoms or cravings for opioids if you stop taking them
• becoming more sensitive to pain

You can reduce your risk of experiencing serious side effects by not drinking alcohol, and by avoiding benzodiazepines, cannabis (marijuana) or illegal drugs while you are taking opioid medicines.

Naloxone, an overdose-reversing medication, blocks the effect of opioids on the brain and can be used to reverse an overdose of prescription or illegal opioids. Naloxone only acts for a short time compared with other opioids, so care needs to be taken so that the overdose doesn't resume having an effect once the naloxone has ceased working.

It’s common for people who have been revived with naloxone to crave more opioids. Taking more opioids after taking naloxone could cause a second overdose and is particularly dangerous.

Always discuss any side effects caused by prescription opioids with your doctor. They will be able to help you manage the unwanted effects as well as helping you decide if you should continue taking prescription opioids.

If a person is not breathing, or if they are unresponsive, seek help straight away. Call triple zero (000) and ask for an ambulance.

Can prescription opioids be dangerous?

Opioids can cause life-threatening breathing problems, including slow, shallow, unusual or no breathing — even when used as recommended. These problems can occur at any time during use, but some people are at increased risk particularly people:

• who are older
• who take other medicines that have sedating effects such as benzodiazepines
• who drink alcohol while also taking opioid medications
• who have reduced liver or kidney function
• who have diseases that affect their lungs and airways

You are at risk of misuse or addiction regardless of how long you take an opioid for. After taking opioid medications even for just a short while, you can become tolerant to the medicine, meaning that over time you need higher doses to achieve the level of pain relief needed. The higher the dose of opioids you take, the greater the risk that the opioids will have unwanted and potentially fatal effects.

It's also possible to become dependent on opioid medicines, meaning that if you stop taking them you may experience withdrawal symptoms and start craving opioids. Some people can become addicted to opioids, meaning they feel a compulsion to take opioids even if the medicine is having a negative effect. Symptoms of addiction include uncontrollable cravings and inability to control opioid use even though it's having negative effects on personal relationships or finances.

Every day in Australia, 3 people die from opioid-related harm and nearly 150 people are hospitalised for the same reason.

What is being done to minimise the harm caused by opioid use in Australia?

The Australian Government is working with healthcare professionals to reduce harm caused by prescription and non-prescription opioids. Doctors carefully examine the reasons people are prescribed opioids and check if there are other treatments that could serve them better.

The number of doses of opioid medications in some packs initially prescribed to people for short-term pain relief has been reduced to decrease the risk of harm from unused opioids. Larger pack sizes are still available for people who need them.

If you require opioid treatment for a long period of time, such as if you have cancer or are receiving palliative care, you'll still be able to receive your medication in the same way, with the same pack sizes, as you do now.

If you require opioids for the long-term treatment of chronic non-cancer pain, your doctor will still be able to prescribe your opioid medicines. However, you may be referred to a pain specialist or a different prescriber for a clinical review. Talk to your doctor for more information.

Tips for safe opioid use

If you are taking prescription opioid medicines, there are ways to help keep yourself safe:

• Only use medicines that have been prescribed for you and take them exactly as prescribed by your doctor.
• Don't consume alcohol, benzodiazepines, cannabis or illegal drugs while taking opioid medicines.
• Learn how naloxone can be used to reverse an overdose (including accidental overdose) and share this information with those close to you.
• Discuss any side effects you experience with your doctor.
• Talk to your doctor if your pain is not being controlled by the medicines you are prescribed.

If you have opioid medicines at home that you don't need anymore, you can return them to any pharmacy for safe disposal.

When to see your doctor

If you are taking a prescription opioid you should check in with your doctor frequently to make sure that it is still the best treatment option for you.

If you feel that the opioid you were prescribed is not helping with your pain, it is important to discuss this with your doctor. Your doctor may recommend a different approach to managing your pain and may also help you to gradually stop taking opioid medicines. You should not change the dosage you are taking without speaking to your doctor first.

If you want to stop taking an opioid medicine, discuss it with your doctor. You may need to reduce your dosage gradually.

Opioid medications can cause some serious side effects, including the slowing of heart rate and breathing.

If a person is not breathing, or if they are unresponsive, seek help straight away. Call triple zero (000) and ask for an ambulance.

Watch this video from NPS MedicineWise: Australians talk about their experiences with seeking help for pain, communicating with health professionals and being involved in support groups.

Are you concerned about someone else taking prescription opioids?

If you are concerned about someone else who is taking opioid medicines, you may feel uncomfortable raising the issue with them. Show the person you are speaking to that you have their best interests in mind. Encourage them to seek support from a doctor who will consider all of the options available to treat pain, including non-medicine-based options.

Resources and support

• Call 1300 MEDICINE (1300 633 424) to talk about the medicines you are taking for your pain.
• Discuss your pain on the Pain Link helpline (1300 340 357), which is staffed by volunteers with personal experience of chronic pain.
• Go to Painaustralia to find pain services and programs in your area.
• Learn more about prescription opioids on Choosing Wisely.