On this page: Opioids | Common questions about opioids | Other medicines | Key points
Opioids are commonly used for pain that is hard to ignore or feels very severe. Moderate pain may be a pain score of 4–6 (out of 10), and moderate to severe pain may be a score of 6–10.
There are many different types of opioids, and these need to be prescribed by a doctor.
Codeine is often used for moderate pain. Codeine is broken down in the body into morphine. However, one in 10 people find they don’t get any pain relief as they cannot convert codeine. If taking Panadeine® or Panadeine Forte® does not offer more relief than paracetamol, let your doctor know as you may need other opioids.
Strong opioids, such as morphine, oxycodone, hydromorphone, methadone and fentanyl, are often effective for moderate to severe pain, and can be used safely if taken as prescribed.
Commonly used opioids are listed in the table below. They either release the morphine slowly and control your pain for long periods, or release the morphine quickly to control pain for short periods.
Working out the dose
As people respond differently to opioids, the dose is worked out for each person based on their pain level. It’s common to start at
a low dose and build up gradually until the pain is well controlled. Sometimes this can be done more quickly in hospital or under strict medical supervision.
Opioids commonly used for moderate to severe pain
- MS Contin®
- MS Mono®
- Tramal/Tramal® SR
- Zydol/Zydol™ SR
Side effects of opioids
Opioids can affect people in different ways. It can take a few days
to adjust to taking strong pain medicines. You may have some of
the following side effects:
Most people regularly taking opioid medicines
experience trouble passing stools (constipation). Your treatment
team will suggest or prescribe a suitable laxative to take at the
same time as the pain-killers. You may also be given a stool
softener. Other ways to help manage constipation include drinking
6–8 glasses of water a day, eating a high-fibre diet and getting
some exercise, but these may be difficult if you’re not feeling well.
Feeling sleepy is typical, but this usually lasts for
only a few days until the pain relief dose is stable. Tell your doctor
or nurse if it lasts longer as you may have to change medicines.
Alcohol is likely to increase drowsiness and is best avoided. See common questions about opioids for concerns about driving.
Your body may feel physically tired, so you may need
to ask family or friends to help you with household tasks or your
other responsibilities. Rest is important, but it’s also beneficial to
do some light exercise or activity, such as stretches or going for a
short stroll. This helps you maintain a level of independence and
can give you some energy.
Feeling sick – This usually passes when you get used to the dose,
or can be relieved with other medicines. Sometimes a change in
the type of opioid is necessary.
This usually passes when you get used to the dose,
or can be relieved with other medicines. Sometimes a change in
the type of opioid is necessary.
Opioids can reduce the amount of saliva in your
mouth, which can cause tooth decay or other problems. Chewing
gum or drinking plenty of liquids can help. Visit your dentist
regularly to check your teeth and gums.
If you have itchy skin, sometimes it may feel so
irritating that it is painful. A moisturiser may help, or ask your
doctor if there is an anti-itch medicine available or if you
can try a different opioid for your pain.
You may not feel like eating. Small, frequent
meals or snacks and supplement drinks may help. If the loss in
appetite is ongoing, see a dietitian for further suggestions.
Confusion or hallucinations
This is rare. It is important to
tell your doctor immediately if this occurs.
If you stop taking opioids suddenly, you
will usually have withdrawal symptoms or a withdrawal response.
This may include agitation, nausea, abdominal cramping, diarrhoea,
heart palpitations and sweating. To manage the chance of side
effects, your doctor will decrease your dose gradually to allow your
body to adjust to the change in medicine. Don’t reduce your dose
or stop taking opioids without talking to your doctor first.
Talk to your health care team often about any side effects you’re
having. If needed, they can change your medicines or the doses.
Common questions about opioids
Most people have questions about taking opioid medicines.
Some common questions that may come up are answered on the
following pages. Your doctor, nurse practitioner or nurse can also
discuss any concerns you have.
If you are caring for someone with cancer pain, you may have
some other specific questions about opioids. See caring for someone with cancer.
Will I become addicted to opioids?
No – when people take morphine or other opioids only to
relieve pain, they are unlikely to become addicted to the
medicines. However, after some time, the body gets used to
opioids and if they are stopped suddenly, people may have
withdrawal symptoms (see previous page). This means you
have developed a tolerance, but it is not a sign of addiction.
Health professionals will closely monitor your use to maintain
effective pain relief and avoid potential side effects. They
will adjust the dose if necessary. However, a person who
has already had a drug addiction problem may be at risk of
addiction if opioids are used for cancer pain relief.
Taking opioids for pain relief is different to an addiction. Someone
with a drug addiction problem takes drugs to satisfy physical or
emotional needs, despite the drugs causing harm.
Will I need to have injections?
Not necessarily. Strong pain relievers are usually given by
mouth in either liquid or tablet form. If you’re vomiting,
opioids can be given via the rectum as a suppository, by a
small injection under the skin (subcutaneously), using a skin
patch or in lozenge form. See a list of the different
ways medicines are taken.
Opioids can be injected into a vein for short-term pain
relief, such as after surgery. This is called intravenous opioid
treatment and is given in hospital.
If I start opioids too soon, will they be less
Some people try to avoid taking pain medicine thinking it
is better to hold out for as long as possible so it works better
later. However, this usually makes the situation worse because
the pain perception of the brain and nervous system changes
and pain becomes entrenched, needing more opioids. It is
better to take medicine as prescribed rather than just at the
time you feel the pain.
If I’m given opioids, does that mean my
cancer is advanced?
People with cancer at any stage can develop severe pain that
needs to be managed with strong pain medicine, such as
morphine. If you have a strong pain-killer, this doesn’t mean
you will always need to take it. If your pain improves, you
may be able to take a milder pain-relieving drug.
What if I get breakthrough pain?
While breakthrough pain is relatively common among
people diagnosed with cancer, this sudden flare-up of pain
can be distressing.
You might get breakthrough pain even though you’re taking
regular doses of medicine. This breakthrough pain may last
only a few seconds, several minutes or hours. It can occur if
you’ve been more active than usual or you’ve strained yourself.
Sometimes there seems to be no reason for the extra pain.
You need to talk to your health care team who will advise you
on how to cope with breakthrough pain. They will usually
suggest you take your pain medicine as well as another drug
to help with the breakthrough pain. An extra, or top-up, dose
of a short-acting opioid (immediate release opioid) will be
prescribed to treat the breakthrough pain. The dose works
fairly quickly, in about 30–40 minutes.
It is helpful to keep a record of how many extra doses you need
so your doctor can monitor your overall pain management.
If you find your pain increases with some activities, taking an
extra dose of medicine beforehand may help.
"I have an intrathecal pump, which is filled every 10 days
by a community nurse. I also take breakthrough medication,
but some days I don’t need any. You can never tell. The
pain is mysterious." – Kate
Will the opioids still work if my body gets
used to them?
People who have used opioids for a long time will sometimes
become tolerant to the original dose. This means their doctor
will need to increase the dose to achieve the same pain relief.
Your dose of opioids may also be increased if your pain gets
worse. There is no benefit in saving the pain control until the
pain is severe.
Can I drive while using opioids?
Doctors have a duty to advise patients not to drive if they are
a risk to themselves or others. During the first days of treatment,
you may be less alert, so driving is not recommended. Once the
dose is stabilised, you may want to consider driving. Seek your
doctor’s advice and keep the following in mind:
- Don’t drive if you’re tired, you’ve been drinking alcohol,
you are taking other medicine that makes you drowsy, or
road conditions are bad.
- If you have a car accident while under the influence of a
drug, your insurance company may not pay out a claim.
- Special rules and restrictions about driving apply to people
with brain tumours, including secondary brain cancer, or
people who have had seizures. For more information, talk to
your doctor or download a copy of Brain Tumours and
Driving: A guide for patients and carers from the Neurological
Society of Australasia website.
Can I stop my medicine at any time?
You should only reduce your dose or stop taking opioids in
consultation with your health care team. If your pain gets
better, you may end up needing less or no pain medicine.
Morphine and other opioids will need to be decreased
gradually to avoid side effects that may occur if you were
to stop taking them suddenly. Withdrawal side effects can
include flu-like symptoms or nausea.
You may be prescribed other medicines to help relieve your pain.
These are known as adjuvant drugs or adjuvant analgesics because
they are prescribed with opioids. While they are not designed to
control pain, they may be used for this purpose, and they often
work well for nerve pain. Adjuvant drugs can be added during any
stage of diagnosis and treatment.
The most common types of adjuvant drugs prescribed are
antidepressants and anticonvulsants. See the table on the opposite
page for a full list. These medicines are usually given as a tablet
or an injection into a vein.
Some adjuvant drugs take a few days to work, so opioids are used
to control the pain in the meantime. If you are taking an adjuvant
drug, it may be possible for your doctor to lower the dose of the
opioids. This may mean that you experience fewer side effects
without losing control of the pain. Ask your doctor if the adjuvant
drugs are likely to cause side effects.
| Generic names
|Type of pain
burning nerve pain,
pain, electric shocks
burning or shock-like
|muscle spasms with severe pain
headaches caused by
cancer in the brain, or pain
from nerves or the liver
|bone pain (may also help
prevent bone damage
||muscle spasm, especially
with spinal cord injury
||bone pain (may also help
prevent bone damage
|local anaesthetic (requires careful monitoring)
||severe nerve pain
chemotherapy and hormone
therapy are used to relieve
pain, usually by removing or
shrinking the tumour, or by
stopping its growth. For other
types of pain, or while these
treatments are taking effect,
medicines are usually given.
- Take precautions when
managing or storing your
medicines to avoid potentially
- Pain relief can be mild,
such as paracetamol and
drugs (NSAIDs), or strong, such
- Opioids are generally used for
pain that is hard to ignore or
feels very severe. As a general
guide, moderate pain may be
a pain score of 4–6 (out of 10),
and moderate to severe pain
may be a score of 6–10.
- Medicines can be given in
the form of a tablet, liquid,
lozenge, skin patch, injection
- Medicines may cause different
side effects. Tell your doctor
or nurse about the side effects
you experience so they can
help you manage them.
- Other medicines, such as
antidepressants or steroids,
may be given with opioids
to make them work more
effectively. These are called
adjuvant drugs or adjuvant
- Most people (and their
families) have questions
about taking pain medicines.
Talk to your health care team
about any concerns you have,
such as addiction, driving or
Reviewed by: Dr Melanie Lovell, Clinical Ass Prof, Medicine, Northern Clinical School, Sydney Medical School, University of Sydney, and Palliative Medicine Consultant Physician, Greenwich Hospital, NSW; Nathaniel Alexander, 13 11 20 Consultant, Cancer Council NSW, NSW; Anne Booms, Palliative Care Nurse Practitioner, Canberra Hospital, ACT; Dr Roger Goucke, Consultant, Department of Pain Management, Specialist Pain Medicine Physician, Sir Charles Gairdner Hospital, and Clinical Ass Prof, School of Medicine and Pharmacology, University of Western Australia, WA; John Marane, Consumer; and Dr Jane Trinca, Director, Barbara Walker Centre for Pain Management, St Vincent’s Hospital, VIC.