Morphine
NHS information about the painkiller medicine morphine, including what it's used for, who can take it, how to take it and side effects.
What morphine is for
Morphine is a type of painkiller called an opioid. It's used to treat severe pain, such as pain:
- after an operation
- after an injury
- from cancer
- during end of life care (palliative care)
How to take morphine
Morphine usually comes as tablets, capsules or liquid that you swallow (oral solution).
It can also be given as an injection or through a thin tube into your vein. But this is usually done in a hospital or hospice.
How much morphine you need to take, and for how long depends on why you’re taking it and the type you're taking.
When taking morphine:
- swallow tablets or capsules whole with a glass of water
- use the syringe or cup that comes with the liquid medicine (oral solution) to help you measure the right dose
There are also some tablets you take in a different way, such as tablets that dissolve on your tongue.
Follow the instructions on the packet or leaflet that comes with your medicine to make sure you're taking it correctly. Ask a pharmacist or doctor for advice if you're not sure how to take it or have any problems taking it.
Talk to your doctor if you have taken morphine for a long time and it’s not relieving your pain as well as it used to, or you struggle with pain in between doses of morphine.
If you miss a dose of morphine
If you forget to take a dose of morphine, take it as soon as you remember. But if more than 4 hours has passed since your dose was due, ask a pharmacist or doctor for advice.
If it's nearly time for your next dose, skip the dose you missed and take your next dose at the usual time.
Do not take 2 doses at the same time to make up for a missed dose.
If you take too much morphine
Taking an extra dose of morphine can be dangerous.
Side effects of morphine
Like all medicines, morphine can cause side effects, although not everyone gets them.
Common side effects
Common side effects of morphine include:
- constipation
- feeling sick (nausea) or being sick (vomiting)
- feeling sleepy
- dizziness
- confusion
- headaches
- itchy skin or rash
If you feel dizzy, sleepy or confused after taking morphine, do not drive, ride a bike or use machinery until you no longer have these symptoms.
More about side effects
These are not all the side effects of morphine.
For a full list, see the leaflet that came with your medicine or search for your medicine leaflet on the electronic medicines compendium website.
You can report any side effects you get on the Yellow Card website
Who can and cannot take morphine
Most adults and children aged 6 months and over can take morphine.
But morphine is not suitable for some people. For example, it may not be suitable if:
- you've had an allergic reaction to morphine or another opioid painkiller
- you have a condition affecting your liver or heart
- you have a lung condition, such as asthma
- you have ever had an addiction to alcohol, prescription medicines or illegal drugs
- you have a bowel condition such as a blockage (obstruction)
- you have a head injury
Before taking morphine, tell your doctor if you have any medical conditions.
Breastfeeding and morphine
Tell your doctor if you're breastfeeding. Morphine is not usually used while breastfeeding because there’s a chance it could cause side effects in your baby.
A doctor may recommend it if the benefits outweigh the risks, or they may recommend a different painkiller.
If you're taking morphine while breastfeeding, speak to a healthcare professional or call NHS 111 if you have any concerns about your baby.
Pregnancy and morphine
Tell your doctor if you're pregnant, you become pregnant, or you’re planning a pregnancy while taking morphine.
Morphine is sometimes used during pregnancy if it’s needed. Your doctor will talk to you about the risks and benefits of taking it while you're pregnant.
Taking morphine with other medicines, food and drink
There are some medicines, remedies and supplements that may not mix well with morphine.
These include:
- other opioid painkillers, such as codeine and co-codamol
- a type of antidepressant medicine called a monoamine oxidase inhibitor (MAOI)
- some medicines for nerve pain, fits and seizures, such as gabapentin
- sedative medicines that help with insomnia and anxiety, such as diazepam
- some medicines to help stomach ulcers and reflux
- some medicines that stop you being sick (vomiting)
Before taking morphine, tell your doctor if you’re taking any other medicines, herbal remedies, vitamins or supplements.
Taking morphine with illegal drugs, such as cannabis, cocaine, or heroine can increase the risk of serious side effects.
Food, drink and alcohol with morphine
It's best not to drink alcohol while taking morphine because it can make you sleepy and increase the risk of serious side effects.
Find out more about your medicine
To find out more about your medicine, you can:
- check the leaflet that comes with it
- search for your medicine leaflet on the electronic medicines compendium website
- speak to a pharmacist or doctor for advice
