It's also used for other types of long-standing pain when weaker painkillers no longer work.
Morphine is available only on prescription. It comes as tablets, capsules, granules that you dissolve in water, a liquid to swallow, suppositories (pellets inserted into the bottom) and as an injection. Morphine injections are usually only done in hospital.
- Morphine works by blocking pain signals from travelling along the nerves to the brain.
- The most common side effects of morphine are constipation, feeling sick and sleepiness.
- It's possible to become addicted to morphine, but this is rare if you're taking it to relieve pain under medical supervision.
- It may be best not to drink alcohol while taking morphine as you're more likely to get side effects like feeling sleepy.
- Morphine is also called by the brand names MST, Zomorph, Sevredol, Morphgesic, MXL or Oramorph.
Who can and can't take morphine
Morphine can be taken by children and adults of all ages. However babies, young children and older people are more likely to get side effects.
Morphine is not suitable for some people. Tell your doctor before starting the medicine if you have:
- had an allergic reaction to morphine or any other medicines in the past
- breathing difficulties
- a lung problem
- an addiction to alcohol
- an illness which causes seizures
- a head injury
- low thyroid levels
- adrenal gland problems
- kidney or liver problems
- an enlarged prostate
- low blood pressure
- myasthenia gravis (a rare illness that causes muscle weakness)
Morphine is generally not recommended in pregnancy. Tell your doctor before taking morphine if you're trying to get pregnant, are already pregnant or if you're breastfeeding.
How and when to take
It's important to take morphine as your doctor has asked you to.
Take morphine with, or just after, a meal or snack so it's less likely to make you feel sick.
Different types of morphine
Morphine comes as:
- granules (that you dissolve in water to make a drink)
- a liquid that you swallow
Morphine suppositories are useful if you can't swallow tablets or liquids.
Morphine liquid, suppositories, injections and some morphine tablets and capsules are fast-acting. They're used for pain which is expected to last for a short time. Fast-acting morphine is often used when you start taking morphine to help find the right dose.
Morphine granules and some morphine tablets and capsules are slow-release. This means the morphine is gradually released into your body over either 12 or 24 hours. This type of morphine takes longer to start working but lasts longer. It's used for long-term pain.
Sometimes you may take both a fast-acting morphine and a slow-release morphine to manage long term pain and sudden flares of pain that break through the long-acting medicine.
Morphine does not come as a skin patch. However, there are skin patches containing morphine-like painkillers such as fentanyl.
How often will I take it?
How often you take it depends on the type of morphine that you've been prescribed.
You can choose to take your morphine at any time of day but try to take it at the same time every day and space your doses evenly. For example, if you take morphine twice a day and have your first dose at 8am, take your second dose at 8pm.
- fast-acting tablets and capsules – usually 4 to 6 times a day
- slow-release granules, tablets and capsules – usually once or twice a day
- liquid – usually 4 to 6 times a day
- suppositories – usually 4 to 6 times a day
- injections – usually 4 to 6 times a day (sometimes in a pump that you control yourself)
It's important to swallow slow-release morphine tablets and capsules whole with a drink of water.
Don't break, crush, chew or suck morphine slow-release tablets or capsules. If you do, the slow-release system won't work and the whole dose might get into your body in one go. This could cause a potentially fatal overdose.
Will my dose go up or down?
Usually, you start on a low dose of morphine and this is increased slowly until your pain is well controlled.
Once your pain is under control, talk to your doctor about swapping to slow-release morphine. This may cut down the number of doses you have to take each day.
When you stop taking morphine your dose will go down gradually, especially if you've been taking it for a long time.
What if I forget to take it?
This will vary depending on which type of morphine you're taking.
If you forget to take a dose, check the information on the patient information leaflet inside the packaging or ask your pharmacist or doctor for advice on what to do.
Never take 2 doses at the same time to make up for a forgotten one.
If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to remember to take your medicine.
What if I take too much?
Taking too much morphine can be dangerous.
If you've taken an accidental overdose you may feel very sleepy, sick or dizzy. You may also find it difficult to breathe. In serious cases you can become unconscious and may need emergency treatment in hospital.
The amount of morphine that can lead to an overdose varies from person to person.
If you need to go to hospital, take the box or leaflet inside the packet plus any remaining medicine with you.
Where to store morphine
If you're prescribed morphine, it's particularly important that you:
- store it properly and safely at home
- keep it out of the sight and reach of children
- never give your medicine to anyone else
Return any unused morphine to your pharmacist who will dispose of it.
Like all medicines, morphine can cause side effects in some people but many people have no side effects or only minor ones.
The higher the dose of morphine the more chance that you will get side effects.
Common side effects
Common side effects happen in more than 1 in 100 people. Talk to your doctor or pharmacist if the side effects bother you or don't go away:
- feeling and being sick
- dizziness and vertigo (a sensation of spinning)
- feeling sleepy
- itchiness and rash
Serious side effects
Serious side effects happen in less than 1 in 100 people. Tell your doctor if you get:
- heart problems
- breathing difficulty or short shallow breathing
- muscle stiffness
- low blood pressure which can make you feel dizzy, tired and have low energy
Serious allergic reaction
In rare cases, it’s possible to have a serious allergic reaction to morphine.
A serious allergic reaction is an emergency. Contact a doctor straight away if you think you or someone around you is having a serious allergic reaction.
The warning signs of a serious allergic reaction are:
- getting a skin rash that may include itchy, red, swollen, blistered or peeling skin
- tightness in the chest or throat
- having trouble breathing or talking
- unusual hoarseness
- swelling of the mouth, face, lips, tongue, or throat
These are not all the side effects of morphine. For a full list see the leaflet inside your medicines packet.
You can report any suspected side effect to the UK safety scheme.
How to cope with side effects
What to do about:
- constipation – try to eat more high-fibre foods such as fresh fruit and vegetables and cereals. Try to drink several glasses of water or other non-alcoholic liquid each day. If you can, it may also help to do some gentle exercise. Speak to your doctor about medicine to help prevent or treat constipation caused by morphine if your symptoms do not go away.
- feeling sleepy, tired or dizzy – these side effects should wear off within a week or two as your body gets used to morphine. Talk to your doctor if they carry on for longer.
- feeling sick or vomiting – take morphine with or just after a meal or snack to ease feelings of sickness. This side effect should normally wear off after a few days. Talk to your doctor about taking anti-sickness medicine if it carries on for longer.
- dry mouth – try chewing sugar-free gum or sucking sugar-free sweets. Your doctor may also prescribe an artificial saliva substitute to keep your mouth moist. This comes as a spray, gel or lozenge.
- breathing problems – speak to your doctor, as starting with a lower dose and increasing it gradually can help prevent breathing problems.
Don't take any other medicines to treat the side effects of morphine without speaking to your pharmacist or doctor.
Pregnancy and breastfeeding
Morphine is generally not recommended during pregnancy and while breastfeeding.
In early pregnancy, it's been linked to some problems for your unborn baby. If you take morphine at the end of pregnancy there's a risk that your newborn baby may get withdrawal symptoms or be born addicted to morphine.
However, it's important to treat pain in pregnancy. For some pregnant women with severe pain, morphine might be the best option. Your doctor is the best person to help you decide what's right for you and your baby.
For more information about how morphine can affect you and your baby during pregnancy see the BUMPS leaflet.
Morphine and breastfeeding
Morphine is not usually recommended if you're breastfeeding. Small amounts of morphine pass into breast milk and can cause breathing problems in the baby.
Cautions with other medicines
Some medicines and morphine interfere with each other and increase the chance that you will have side effects.
Tell your doctor if you are taking any medicines:
- to help you sleep
- for depression – some types can't be taken with morphine
- for high blood pressure
- to help stop you feeling sick or vomiting
- to treat symptoms of an allergy
Mixing morphine with everyday painkillers
Some everyday painkillers that you can buy over-the-counter from pharmacies contain codeine, which is a similar medicine to morphine. Codeine-containing painkillers from pharmacies include co-codamol, Nurofen Plus and Solpadeine.
Do not take codeine-containing painkillers that you can buy alongside prescribed morphine (and prescribed codeine). You will be more likely to get side effects.
Mixing morphine with herbal remedies and supplements
It's not possible to say that complementary medicines and herbal teas are safe to take with morphine. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.
How does morphine work?
How long will it take to work?
Can I become addicted to morphine?
How will I know if I'm addicted?
Will I get withdrawal symptoms when I stop taking it?
Is morphine a controlled medicine?
Can I drink alcohol with it?
Are there other painkillers I can try?
Will it make me so sleepy I can't function?
Is morphine only used at the end of life?
Can children take morphine?
Can I drive or ride a bike?
Will recreational drugs affect it?