Updated January 2023

What is an Opioid?

Download button - information sheet(Examples of brand names: Durogesic, Endone, Jurnista, Kapanol, MS Contin, Norspan, Oxycontin, Palexia, Panadeine Forte, Tramal, Targin, Temgesic)

Opioids are strong pain-relieving medicines naturally found in the opium poppy plant. Some prescription opioids are made from the plant directly, and others are made by scientists in labs using the same chemical structure.

Opioids contain chemicals that bind to receptors in the brain, spinal cord, and other areas of the body. They relax the body and reduce the sending of danger messages to the brain, decreasing the feeling of pain.

They are usually used on a short-term basis in the management of acute pain or in cancer pain and have a very limited role in the management of chronic musculoskeletal pain.

  • All opioids must be prescribed by a doctor.
  • Opioids are available in different forms, including: tablets, capsules, lozenges, liquids and skin patches.
  • Opioids come in different strengths.
  • Treatment usually starts with a low dose.

Opioid products differ in:

  • how fast they can relieve pain.
  • how long their effects last.

Some products release the opioid into the body quickly (immediate or fast release products). They provide fast pain relief but the effects usually only last for a few hours (4-6 hours).

Some products release the opioid into the body slowly (modified-, slow-, extended-, prolonged- or controlled release products). Each dose may give slower pain relief, but the effect may last for longer (e.g. 12-24 hours).

Opioid skin patches are designed to have a stable effect on pain for 3 to 7 days.

What benefit can you expect from your treatment?

Opioids generally do not give total pain relief. They may be used together with other pain-relieving medicines and should be used with non-medicine therapies as part of an overall pain management plan. Opioids work best to relieve short-term pain in some people. The longer you use an opioid, the less well it works, and you may need more to feel the same level of pain relief. Sometimes opioids can even make the pain worse (see ‘opioid induced hyperalgesia’ under Side Effects). Because not all patients experience benefit from taking an opioid, your doctor will usually prescribe an opioid for a trial period (up to 8 weeks). The doctor will assess how well the opioid relieves your pain and improves your function and quality of life. The doctor will also monitor for side effects. Depending on your response to the opioid in the trial period, the doctor will decide in consultation with you whether treatment for a longer period of time would be appropriate.

How is an opioid taken?

It is important to take/apply opioids exactly as directed by your doctor. Please read the instructions provided by your doctor carefully to ensure that you are taking/using your opioid correctly.

When should it be taken?

How often you take/apply an opioid depends on the one you have been prescribed. Ask your doctor or pharmacist if you are uncertain about how often to take/apply your opioid. Opioids can be taken without regard to food.

What is the dosage?

The dosage of your opioid will depend on your situation. Your doctor will adjust the dose depending on the type of opioid and your response to the opioid.

Can other medicines be taken with opioids?

Opioids can and should be used in combination with other pain-relieving medicines such as paracetamol and non-steroidal anti-inflammatory drugs (NSAIDs). Opioids can interact with other medicines and alcohol. Check with a doctor or pharmacist before taking other medicines and alcohol while on opioids. You should not take more than one long-acting opioid at a time. If you are taking more than one long-acting opioid, please discuss the ongoing use with your doctor.

How long is the treatment continued?

Due to the potential for side effects and limited benefit for pain relief in chronic non-cancer pain (such as arthritis and back pain), it is recommended that opioids be used at the lowest possible dose for the shortest possible time.

Stopping or lowering your opioid dose: You should not suddenly stop taking your opioid. If you want to stop taking your opioid you should discuss this with your doctor who can provide you with a plan to slowly reduce your dose to reduce withdrawal symptoms. The time it takes depends on how much you take, how long you have been taking it for and your own circumstances. More information can be found here https://www.nps.org.au/consumers/opioid-medicines#plan-for-reducing-or-stopping-opioids

Side effects

Tell your doctor if you are concerned about possible side effects. A reduction in dose or change to another opioid may decrease the side effects. Alternatively, your doctor may stop the opioid and recommend a different pain-relieving medicine with fewer potential side effects.

Most common possible side effects: Constipation, nausea and vomiting: A high-fibre diet, plenty of fluids and exercise can help to prevent constipation. Sometimes a laxative is recommended while you are taking an opioid to prevent constipation. Nausea and vomiting can be common when you first start taking an opioid, but it usually stops after a few weeks of treatment.

Drowsiness: You can feel drowsy or sleepy when you first start an opioid or when the dose is increased. The drowsiness usually decreases within a few weeks. Clouded thinking, headache, itchy skin, sweating, dry mouth and depression can occur.

Physical dependence: This means that your body adjusts to the opioid and withdrawal symptoms will occur if the opioid is suddenly stopped. Common withdrawal symptoms include: sweating, anxiety, agitation, muscle aches, nausea and diarrhoea. Dependence can develop if you take an opioid every day for more than a few days. There is potential for the abuse of opioids and strong psychological dependence (addiction). Do not give or sell your opioid to another person or take an opioid that was not prescribed for you.

Tolerance: This means that the pain-relieving effect of a stable dose of an opioid decrease over time so higher doses of the opioid may be needed to get the same pain-relieving effect over time. This must be carefully managed by a doctor.

Less common or rare possible side effects:

Respiratory depression is a breathing disorder which causes slow and ineffective breathing. It is an infrequent but serious side effect of opioids and can lead to death. Feeling very sleepy and being unable to stay awake is usually one of the first signs of respiratory depression. Stop taking the medicine and contact your doctor immediately if you have these symptoms.

Opioid induced hyperalgesia (OIH) is a less common side effect of opioids. OIH usually occurs when high doses of opioids have been taken over a long period of time. In OIH, the pain actually gets worse when the dose of the opioid is increased. The only way to manage OIH is to reduce the dose of the opioid.

Long-term side effects

Hormonal effects are a potential long-term side effect of opioids. In males, this can include low testosterone levels, impotence and decreased sexual drive. In females, there may be an absence of menstrual period.

What precautions are necessary?

Do not ever crush, break, or chew slow release opioids. This can be dangerous and result in overdose. When using opioid patches, heat may increase the release of opioid from the patch and hot skin may absorb the drug faster and can result in overdose. Please seek advice from your doctor if you develop a fever. Avoid the use of devices which can increase the external body temperature especially where the patch is applied for e.g. hot water bottles or heat packs.


Opioid overdose is opioid poisoning. It’s a life-threatening medical emergency. Your risk of overdose is higher if you: use higher opioid doses, use more than one opioid at the same time, do not follow the directions for use of your opioid, use your opioid with alcohol, illegal drugs, or medicines that can make you feel sleepy. Opioid overdose can happen by accident. Naloxone is a medicine that reverses the effects of opioids for a short time. It helps the person with overdose to breathe while waiting for the ambulance. Ask your healthcare professional about naloxone for opioid overdose.

Driving and use of machinery:

Opioids may impair your ability to drive and operate machinery, particularly at the beginning of treatment and if the dose is increased. Do not drive or operate machinery if you are affected.

Use with other medicines:

Opioids can interact with other medicines. You should tell your doctor (including your general practitioner, rheumatologist, and other health professionals) about all medicines you are taking, including herbal and naturopathic medicines. This includes over-the-counter medicines. People taking opioids should be cautious when using medicines that can cause drowsiness, such as benzodiazepines (e.g. diazepam (Valium) or temazepam (Temaze). Other medications used for arthritis can generally be taken with opioids. Please check with your doctor or pharmacist if you are unsure.

Use with alcohol

Alcohol can increase the drowsiness and clouded thinking caused by opioids. You should avoid alcohol while taking opioids.

Use in pregnancy and breastfeeding

Check with your doctor before taking opioids during pregnancy and breastfeeding. Some opioid analgesia (e.g. tramadol) may be appropriate depending on your situation. Opioids can cause respiratory depression and/or withdrawal effects in newborn babies. Codeine should be avoided in breastfeeding. Occasional doses of other opioids are safe but repeated doses should be used with caution. The baby should be monitored for sleepiness and other adverse effects. More detailed information is available here.

How to store opioids

Store opioids in a cool, dry place, away from direct heat and light (e.g. not in the bathroom). Keep all medicines out of reach of children.

Opioid brand names

Long-Acting Opioids

Generic/drug name Brand names
Buprenorphine Norspan
Fentanyl Denpax, Durogesic, Dutran, Fenpatch
Hydromorphone Jurnista
Methadone Physeptone
Morphine Kapanol, Momex SR, MS Contin, MS Mono
Oxycodone (+naloxone) Oxycontin, (Targin)
Tapentadol Palexia SR
Tramadol Durotram XR, Tramal SR, Tramedo SR, Zydol SR

Short-Acting Opioids

Codeine Aspalgin, Codalgin, Codalgin Forte, CodapaneForte, Nurofen Plus, Panadeine, Panadeine Forte, Panafen Plus, Prodeine Forte
Morphine Ordine liquid, Sevredol
Oxycodone Endone, Oxynorm
Tapentadol Palexia IR
Tramadol Tramal, Tramedo, Zydol

Note: This may not be a comprehensive list – ask your pharmacist or doctor for more information.