Skip Ribbon Commands
Skip to main content

Managing Pain After Your Surgery

Changi General Hospital Logo | Preoperative Anaesthesia Assessment Clinic (PAAC)

Favourites Remember to add this page to your Health Buddy ‘Favourites’ for easy access before your surgery. Simply click on the ‘star’ icon at the top right of Health Buddy app.

This leaflet explains about pain relief after surgery. There are many effective treatments to help keep you comfortable after your surgery. The different ways of relieving pain will be explained before your surgery by the doctors and nurses looking after you. The most suitable one for you and your type of surgery will be provided.

What is pain and how can it be measured?

Pain is the unpleasant sensation that people experience after an injury or surgery. You will be asked to tell the doctors and nurses about any pain that you have. They will ask you about the severity of the pain at rest and on movement, such as deep breathing, coughing or sitting out of bed.

Why do we treat pain?

Good pain relief is very important and has many benefits such as:

  • Greater comfort while you recover from surgery
  • Quicker recovery as breathing exercises, mobilising and physiotherapy can all be managed with less discomfort
  • Reduces the complications of surgery such as chest infections and blood clots

How will my pain be treated?

There are many different ways to control pain and sometimes combinations of treatments are used to get the best results. The effectiveness of your pain relief will be assessed at regular intervals and adjustments to the treatment can be made if required. We aim for patients to be able to cough, breathe deeply and move around the ward without experiencing significant discomfort. It is much easier to relieve pain if it is managed before it gets too severe, therefore, you should ask for help when you experience pain and continue your treatment regularly.

The available methods of pain relief are:

  • Tablets and liquids
  • Injections
  • Patient controlled analgesia (PCA)
  • Nerve blocks (including Epidural) catheters (information in other leaflet)

Tablets and liquids

If you are able to eat and drink, the most convenient way to take painkillers is by mouth. We know the combinations of different types of analgesics (painkillers) provide the best pain relief.

If you find swallowing tablets difficult, you need to tell the nurses and doctors looking after you, as soluble or liquid forms are available.


It is prescribed for nearly all patients to take regularly after surgery as research has shown that it can improve the effectiveness of other painkillers. Smaller doses of stronger painkillers can then be used with reduced side effects.

NSAIDS / COX-2 inhibitors (Examples- Ibuprofen, Voltaren, Aspirin, Celebrex, Arcoxia etc)

These type of medicines relieves pain at the site of your surgery by reducing the swelling and inflammation. They may be unsuitable if you have stomach ulcers, gastritis, asthma, or are taking blood thinners (please enquire with doctors / nurses for more details about these medications).

If you have had a problem with taking NSAIDs / COX-2 in the past, please let the doctor or nurse know.

If you have severe indigestion, breathing difficulties or severe stomach pain after taking these medicines, stop taking them and let your doctors know.

Most common side effects seen with these medicines include nausea, diarrhoea, headache and dizziness. If these side-effects do not subside or are intolerable, please let your doctor know.

You should only take one type of these medicine at a time. These medicine should always be swallowed whole just after food.

Weak opioids (Tramadol, Codiene)

This medicine is used to treat moderate pain, including pain after surgery.

Occasionally, Tramadol can cause confusion and disturbed thought and sleep patterns. If you experience these symptoms, it is best to stop taking Tramadol and talk to your doctor. Tramadol can affect other medicines you take and make you unwell. Please ensure that your doctor and pharmacist know that you are taking Tramadol.

Strong opioids (Examples- Morphine, Oxycontin, Oxynorm, Targin)

These are stronger pain relief medicine that should be used for breakthrough pain when your regular Paracetamol and NSAIDS / COX-2 are not effective, although they are sometimes prescribed to be taken regularly.

Constipation is a common side effect of opioids. To prevent this, drink plenty of water and increase your intake of fibre by eating regular portions of fruit, vegetables and cereals. If constipation continues to be a problem, you may need to take laxative such as Senna/ Lactulose etc. Other side effects include nausea and drowsiness.

It is an offence to drive when your ability is impaired by medication and you may also invalidate your insurance e.g. opioids can make you drowsy and affect your response time. If in doubt, do not drive. Seek advice from your doctor or pharmacist.

Alcohol should be avoided while taking these medications as it may increase drowsiness.


When patients are experiencing a lot of discomfort, an injection of strong painkiller can be given either just under the skin (subcutaneous), into a muscle (intramuscular) or a vein (intravenous). These can be given at regular intervals or as required. Sometimes a small plastic tube (intravenous cannula) will be inserted into the vein which will prevent the need for several injections.

Patient Controlled Analgesia (PCA)

PCA is a system that allows you to be in control of your own pain relief. A device containing a strong painkiller such as Morphine is connected to a small plastic tube (intravenous cannula) in the vein, usually in your hand or arm. The device enables you to control the pain via a button on the PCA handset.

  • When you press the button, a small dose of painkiller is delivered into the vein.
  • PCA allows you to give yourself small amounts of the pain killing drug when you require it and avoids any wait to get analgesia and also any further injections.
  • You can press the button as often as you require. It is important not to let the pain build up before pressing the button.
  • The device has a safety mechanism to make sure that you cannot give yourself too much painkiller. It will only allow a measured dose to be delivered every 5 minutes.
  • PCA is very safe as long as you press the button, as only you know the pain you can feel and how much painkiller you need to relieve it and much effect the medicine is having. The nurses will check and record at regular intervals how much of the painkiller you are using.
  • If you are using the PCA and continue to experience pain, you must tell the nurse looking after you.

Morphine-like medicine can produce some unwanted side effects, the more common of which are:

  • Tiredness / drowsiness
  • Light-headed feeling
  • Vivid dreams
  • Itchiness
  • Nausea, vomiting
  • Constipation

Treatments are readily available to treat any unpleasant side effects so it is very important for you to report any symptoms.

You can have PCA until you are able to take medicines by mouth.

Patients sometimes worry about becoming addicted to strong medicines like Morphine but when used to treat pain after surgery it should not cause addiction.

Peripheral Nerve Block and Central and Central Neuraxial Block

For more in depth information regarding Peripheral Nerve Block and Central Neuraxial Block (including Epidural and Spinal), please refer to Pre-Operative Information for Lower Limb and Upper Limb.

Painkillers to take at home

When you are ready to be discharged from hospital, the ward doctors will write a prescription for painkillers along with other medicines that they want you to continue at home.

You should take the painkillers as prescribed and at the prescribed intervals. If you are not sure about how or when to take the painkillers, please ask the ward nurses before you are discharged. The pain should improve with time and the painkiller can then be discontinued.

Once you have been discharged from hospital, if you have any problems with pain, you should contact the team taking care of you in the hospital.

The Pain Service

We aim to provide the safest and best pain relief for all patients after surgery. To achieve this, we have an acute pain service provided by a team of doctors and specialist nurses. The team is available weekdays to advise and answer any questions that you may have about pain relief. If you would like to speak to one of the team you can ask the ward nurses to contact us.