Opioids: risk of dependence and addiction

New recommendations following a review of the risks of dependence and addiction associated with prolonged use of opioid medicines (opioids) for non-cancer pain. Before prescribing opioids, discuss with the patient the risks and features of tolerance, dependence, and addiction, and agree together a treatment strategy and plan for end of treatment.

Advice for healthcare professionals:

  • opioid medicines (opioids) provide relief from serious short-term pain; however long-term use in non-cancer pain (longer than 3 months) carries an increased risk of dependence and addiction
  • discuss with patients that prolonged use of opioids may lead to drug dependence and addiction, even at therapeutic doses – warnings have been added to the labels (packaging) of UK opioid medicines to support patient awareness
  • before starting treatment with opioids, agree with the patient a treatment strategy and plan for end of treatment
  • explain the risks of tolerance and potentially fatal unintentional overdose, and counsel patients and caregivers on signs and symptoms of opioid overdose to be aware of (see opioids safety information leaflet plus PDF leaflet)
  • provide regular monitoring and support especially to individuals at increased risk, such as those with current or past history of substance use disorder (including alcohol misuse) or mental health disorder
  • at the end of treatment, taper dosage slowly to reduce the risk of withdrawal effects associated with sudden cessation of opioids; tapering from a high dose may take weeks or months
  • consider the possibility of hyperalgesia if a patient on long-term opioid therapy presents with increased sensitivity to pain
  • consult the latest advice and warnings for opioids during pregnancy in the product information and in clinical resources
  • report suspected dependence or addiction to any medicine, including to an opioid, via the Yellow Card scheme

National review of benefits and risks of opioid medicines

More than 20 different opioid medicines (opioids) are authorised for use in the treatment of pain in the UK. The relative potency differs between these medicines. Opioids relieve pain but may not remove pain altogether.

Considerable concern has been raised regarding prescribing rates of opioids in the UK and the awareness of healthcare professionals and patients of the risks of dependence and addiction. This includes Public Health England’s evidence review of dependence and withdrawal associated with some prescribed medicines.

In 2019, the Commission on Human Medicines (CHM) convened an Expert Working Group to examine the benefits and risks of opioids in the relief of non-cancer pain, including information available to healthcare professionals and patients about the risks of dependence and addiction. Following this review, CHM has made recommendations to improve information for prescribers and patients about these risks to protect public health.

To make it clear that a medicine contains an opioid and that there is a risk of addiction (a recognised term by patients) with prolonged use, CHM recommended that the packaging for all opioid medicines in the UK carries the warnings ‘Can cause addiction’ and ‘Contains opioid’. The CHM also recommended including further information on the risk of tolerance, dependence and addiction in the product information.

The changes apply to the following opioids:

Alfentanil Dihydrocodeine Meptazinol Oxycodone Remifentanil
Buprenorphine Dipipanone Methadone Papaveretum Tapentadol
Codeine Fentanyl Morphine Pentazocine Tramadol
Diamorphine Hydromorphone Opium Pethidine -

Tolerance, dependence, and addiction

Product information for opioids in the UK will include consistent warnings of the risks of tolerance and dependence and addiction. Patients may find that treatment is less effective with long-term use and express a need to increase the dose to obtain the same level of pain control as initially experienced. This could indicate that the patient is developing tolerance and dependence.

For all patients, prolonged use of opioids may lead to drug dependence (and in some patients addiction/opioid use disorder), even at therapeutic doses (see resources from the Faculty of Pain Medicine). The risks are increased in individuals with current or past history of substance use disorder (including alcohol misuse) or mental health disorder (for example, major depression). Additional support and monitoring may be necessary when prescribing for patients at risk of opioid misuse.

Typical signs of addiction are:

  • Expression of craving for the drug, even if it is causing adverse effects on overall health
  • Expression of a need for more, or reporting additional use of other pain-relief medicines
  • Taking medicines for reasons other than pain relief
  • Experiencing withdrawal side effects when opioids are stopped suddenly

Withdrawal reactions

Dependence and addiction to opioids are associated with adverse reactions of withdrawal upon sudden cessation of treatment that make it harder to stop taking these medicines. CHM has therefore recommended that before prescribing an opioid a discussion should be held with the patient, to put in place a withdrawal strategy for ending treatment with their opioid medicine.

Withdrawal from an opioid is characterised by shivers, diarrhoea, difficulty sleeping (insomnia), sweating, body aches (myalgia), widespread or increased pain, irritability and agitation, and nausea and vomiting. Other signs and symptoms include restlessness, lacrimation, rhinorrhoea, yawning, mydriasis, palpitations, anxiety, hyperkinesia, tremor, weakness, anorexia, abdominal cramps, and increased blood pressure, respiratory rate, and heart rate.

Tapering doses

To minimise the risk of withdrawal reactions, the dose of opioid should be tapered slowly at the end of treatment. This can take weeks or months, depending on individual response and the dose taken. Healthcare professionals should advise patients not to stop suddenly taking their medicines or try to self-medicate to overcome withdrawal effects. Self-medication with opioids can result in overdose and potentially death.

Hyperalgesia

Some patients can develop hyperalgesia (increased sensitivity to pain) with long-term use of opioids. This might be qualitatively and anatomically distinct from pain related to disease progression or to breakthrough pain resulting from development of opioid tolerance. These symptoms may resolve with a gradual reduction in opioid dose.

Opioids in pregnancy

Opioids readily cross the placenta, therefore if used during pregnancy neonates may become dependent and experience neonatal abstinence syndrome at birth. Extra vigilance is required and appropriate treatment should be made available.

Resources for prescribers and dispensers

We have developed an opioids safety information leaflet on the risks of dependence and addiction (also available as a PDF leaflet). This advice for patients and their families and carers was developed following consultation with a number of stakeholder organisations, charities, and patient groups.

We encourage healthcare professionals to use this information alongside the statutory patient information leaflet supplied with opioid medicines.

Additional guidance is available for healthcare professionals and patients at the following websites:

Report side effects, including dependence

If a patient experiences any side effect related to dependence to a medicine or is recognised by the prescriber to be dependent, CHM encourages prescribers, patients, or carers to report this to the MHRA through the Yellow Card scheme with the term ‘dependence’. Use of this specific term will assist the MHRA to monitor the rates reported in the UK and therefore to further protect public health.

Any other suspected adverse drug reactions associated with opioids should also be reported to the MHRA through the Yellow Card scheme. Report via the Yellow Card website, Yellow Card App (download at iTunes Yellow Card for iOS devices or at PlayStore Yellow Card for Android devices), or some clinical IT systems (EMIS/SystmOne/Vision/MiDatabank).

Article citation: Drug Safety Update volume 14, issue 2: September 2020: 1.

Post-publication note: August 2021

Following user testing, improvements were made in August 2021 to the wording of the opioids safety information leaflet (labelled as Version 2). This update does not change the safety information for opioid medicines.

Published 23 September 2020