Strong opioid medicines for pain relief : University College London Hospitals NHS Foundation Trust

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This page explains what strong opioid medicines are and how they help to relieve
pain. You may be experiencing pain because of your illness or the treatment you are
having. If you have already tried weak opioid medicines but you are still struggling
with pain, your doctor or nurse may suggest a strong opioid.

What are opioid medicines?

Opioid medicines are painkillers that are morphine-based. They come in several strengths (usually described as weak or strong).

There are two main types of strong opioids: short-acting and long-acting. Short-acting opioids usually start working within 30 minutes and wear off after three or four hours. Long-acting opioids provide a background, or continuous, level of pain relief throughout the day and night. It can take up to 12 hours to reach an effective level of pain relief when you first start to take them.

There is no standard dose of strong opioids. The amount needed to control pain varies from person to person.

Morphine

Your doctor or nurse will initially prescribe a short-acting morphine, such as Oramorph® (liquid) or Sevredol® (tablet). They will probably advise you to take it every four hours, but encourage you to take another dose if you are still experiencing pain in between doses (breakthrough pain).

After a few days, and if you need it, your doctor or nurse will also prescribe you a long-acting morphine, such as MST®. This dose will be based on how much short-acting morphine you need. For this reason, it’s important that you tell your doctor or nurse how well the short-acting morphine is working and how often you are taking it. Keeping a diary can help.

Long-acting morphine is taken twice a day and comes as a tablet or capsule.

Things to remember about morphine:

Addiction to morphine is very unlikely if you take it as advised.

Being prescribed morphine does not necessarily mean you are reaching the end of your life.

Being prescribed morphine now does not mean you won’t be prescribed additional pain medication if your pain gets worse in the future.

Oxycodone is similar to morphine and is prescribed and taken in the same way. It comes as a tablet, capsule or liquid.

Your doctor or nurse might suggest oxycodone if:

morphine has been causing you a lot of side effects
you think morphine is no longer working, or
you have problems with your kidneys.

If you have been taking a long-acting morphine, you will be prescribed the equivalent dose of a long-acting oxycodone. But if you haven’t taken an opioid before, your doctor or nurse will initially prescribe you a short-acting oxycodone.

If you continue to experience breakthrough pain while taking a long-acting opioid, your doctor or nurse will also prescribe you a short-acting opioid to help with this.

It’s important that you tell your doctor or nurse if you are experiencing breakthrough pain more than three times per day. This is because you may need to increase your dose of a long-acting opioid.

Side effects of opioids

Opioids can cause constipation so drink plenty of water and include lots of fruit, vegetables and fibre in your diet. If needed, your doctor or nurse may suggest a laxative.
Opioids can also make you feel drowsy. This can happen when you first start taking them and often wears off after a few days. If you are still feeling drowsy after a few days, let your doctor or nurse know.
You may also feel drowsy if you are taking them too often or if the dose is too high.
Opioids can make you feel sick or nauseous. This often settles down after a few days, but your doctor or nurse may prescribe you an anti-sickness tablet to help relieve this.

Please seek advice from your doctor or nurse if you drive or drink alcohol and are
taking an opioid medicine.

If you have any questions about the medicine(s) you have been prescribed, or if you think your medicines are not helping, please talk to your doctor or nurse, or contact the Enhanced Supportive Care team.

Macmillan Support and Information Service

The Macmillan Support and Information Service is located on the ground floor of the University College Hospital Macmillan Cancer Centre. The support and information specialists based in the service provide emotional support, practical advice and information to anyone affected by cancer or a blood condition. They can see patients, their families and friends at any stage of their care. You don’t need an appointment to visit the Macmillan Support and Information Service. The team will see you as quickly as possible.

Tel: 020 3447 8663

Email: uclh.supportandinformation@nhs.net