Certain side effects are common to all opioids.
These are readily managed by appropriate dosing and concomitant use of other agents such as laxatives and anti-emetics.
True allergic reactions are rare.
Must be anticipated and prevented in all patients on weak or strong opioids. Constipation may be less severe in some patients with transdermal fentanyl.
Regular stimulant laxatives must be commenced at the same time as weak or strong opioids. The dose of laxative required may increase as the dose of opioid increases (see chapter: Constipation).
Is a common problem (for around 30%) during the first few days of treatment. If it occurs, haloperidol or metoclopramide are suitable anti-emetics (see chapter: Nausea and Vomiting).
Is rare in patients taking opioids for their analgesic effects.
May occur, but an increase in dose requirement often reflects an increase in pain due to advancing disease. For patients who exhibit tolerance to a particular strong opioid, switching to another strong opioid might be helpful. Seek specialist palliative care advice.
Is rarely a risk when doses are increased by appropriate increments and the patient is reviewed accordingly. Pain is a physiological antagonist to the central depressant effects of opioids. If pain is relieved by alternative methods e.g. radiotherapy or nerve block, a reduction in opioid dose will be required.
Other recognised side effects are:
The latter two are part of a multifactorial syndrome known as neurotoxicity.
Causes a spectrum of symptoms, from mild confusion or drowsiness to hallucinations, delirium, and seizures.
Seek Specialist advice if opioid induced.
May occur with the first few doses, but then can lessen. Caution this may impair fitness to drive, medical advice is advised regarding this if appropriate. Psychostimulant medications can be prescribed to help with this, seek specialist advice.
Twitching or clonic spasm of a muscle or group of muscles. It can be seen in any muscle group/limbs, may vary in severity and can be sporadic or continuous. Consider reducing opioid dose and add an adjuvant or switch to different opioid and consider reduce dose of new opioid by 20-30%.
Reduce opioid dose and add an adjuvant or switch to different opioid and consider reduce dose of new opioid by 20-30%, treat symptomatically with haloperidol.
Confusion / agitation / cognitive impairment.
Treat symptomatically with haloperidol/levomepromazine or newer atypical anti-psychotic in the short term. Consider reducing opioid dose and add an adjuvant (preferably non-psychoactive adjuvant) or switch to different opioid and consider reduce dose of new opioid by 20-30%.
This Guide is intended for use by healthcare professionals and the expectation is that they will use clinical judgement, medical, and nursing knowledge in applying the general principles and recommendations contained within. They are not meant to replace the many available texts on the subject of palliative care.
Some of the management strategies describe the use of drugs outside their licensed indications. They are, however, established and accepted good practice. Please refer to the current BNF for further guidance.
While WMPCPS takes every care to compile accurate information , we cannot guarantee its correctness and completeness and it is subject to change. We do not accept responsibility for any loss, damage or expense resulting from the use of this information.