New HSIB report highlights liquid morphine patient safety concerns

  • 28th April 2022

In this blog Patient Safety Learning considers several key patient safety issues highlighted in a recent investigation by the Healthcare Safety Investigation Branch (HSIB) into unintentional overdose of morphine sulfate oral solution. We argue that in some areas further action is required to prevent the recurrence of incidents of avoidable harm.

A recent investigation report has been published by HSIB intended to improve patient safety in relation to the use of oral morphine sulfate solution (a strong pain-relieving medication taken by mouth).[1]

The investigation focused on the case of Len, who took an accidental overdose of morphine sulfate oral solution. He had previously been diagnosed with Charcot-Marie-Tooth disease, a progressive disease that affects the nervous system, and had been prescribed morphine sulfate by his GP for persistent symptoms of breathlessness and pain following a fall.

Len was prescribed morphine sulfate, which has a concentration of 10mg in 5ml, at a dose of 1.25ml to 2.5ml, to be taken up to every 4 hours when required. His Wife collected his prescription from the pharmacy and subsequently Len took three doses of 5ml (two to four times the suggested dose) over the course of a day.

The next morning, he was taken by ambulance to the local emergency department due to breathing difficulties, thought to be caused by a suspected accidental overdose of morphine, pneumonia and worsening of his Charcot-Marie-Tooth disease. He initially recovered after receiving treatment, but sadly died a short time later. After his death, when the family asked about why he had been prescribed such a high dosage, it was discovered that that Len and his Wife had not seen the dispensing label on the outer packaging which advised that he should take a dose of 1.25ml to 2.5ml.

Findings of the investigation

HSIB’s investigation found that the decision-making process that resulted in Len being prescribed morphine sulfate oral solution had followed national guidance. However, when it came to the prescription of this:

  • The dosage guidance label was on the outer box that contained the morphine sulfate bottle, not on the bottle itself. This label was not seen by Len or his Wife.
  • Len and his Wife read the manufacturers text on the morphine bottle, which showed the strength of the liquid (5ml), which they mistook this for the required dose (1.25ml to 2.5ml).
  • The morphine sulfate bottle came with a measurement aid, a 5ml syringe. With this measure being the same as the strength of the liquid shown on the bottle, this confirmed in the minds of Len and his Wife that the dose was 5ml.

Key patient safety concerns

Patient Safety Learning welcomes the publication of this HSIB report, and the patient safety issues that it highlights. As with all HSIB reports, we publish these on the hub, our learning platform for patient safety.

In this report we believe that there are several patient safety issues that require further consideration, with action needed to prevent incidents of avoidable harm such as this reoccurring in future.

Labelling and measurement aids

The report highlights significant patient safety concerns relating to the packaging of morphine sulfate and the measurement aid this was dispensed with.

Firstly, considering the packaging, the dosage information was contained on a small label on the outer box, but not on the oral solution bottle itself. This appears to have created an error trap for patients, with an assumption that they will read both the box label and the bottle label when looking for dosage information and that they will understand from these what the correct dosage is and act accordingly.

Secondly, there are issues with the measurement aid, in this case a 5ml oral syringe that came with the morphine sulfate. The investigation notes that this measurement is in line with the standard dose for an adult (10mg at 5ml) and older person (5mg at 2.5ml). However due to Len’s health condition, he was prescribed a smaller dose, 1.25ml to 2.5ml. The report states that it was not possible to accurately measure this dose with the syringe provided.

Responding to these issues, HSIB made the following safety observation:

“It may be beneficial if manufacturers of morphine oral solution 10mg in 5ml ensure that any dose measurement aid, if supplied with the medication, is able to measure a full range of possible doses.”

We agree with the intent of this observation but are concerned that alone this will not prevent a similar incident occurring in future. In part this is because the issue with the morphine sulfate labelling differing on the box and bottle is not addressed by this or any other observation or recommendation. Furthermore, regarding manufacturers making changes to the measurement aid, our concern is that there is no assurance that HSIB’s observation will be acted on.

As noted in our report Mind the implementation gap: The persistence of avoidable harm in the NHS, there appears to be no formal framework on a national level to review and act on HSIB’s safety observations.[2] While the steps outlined in this safety observation for manufacturers are desirable, in practice there is no system to implement or monitor this.

Failure by the community pharmacy to participate in the investigation

A crucial point of concern in this case pertains to what information and advice was provided when morphine sulfate was prescribed and dispensed to Len. Understanding this process could be vital in preventing similar incidents occurring in future.

We are dismayed to read that HSIB found that a key organisation involved in this process, the community pharmacy, declined to participate in the investigation. Their report states:

“The investigation tried to engage with the pharmacy on a number of occasions by email, telephone, and recorded post. The investigation also spoke with local commissioners and NHS England and NHS Improvement national pharmacy teams to identify whether any further support could be offered to assist in engaging with the pharmacy. Despite this, the investigation was unable to obtain engagement from the pharmacy and so was unable to complete investigation work that may have assisted in fully considering the patient safety risks presented in Len’s care.”

We consider this to be both a puzzling and unacceptable response by the pharmacy, demonstrating a frankly shocking degree of disregard towards the family affected by this tragic case. Defensive and closed approaches to patient safety investigations severely limit our ability to learn from patient safety incidents, resulting in the continuation of avoidable harm and unnecessary loss of life.

This lack of cooperation underlines the importance of HSIB receiving new powers to compel witnesses by law to give evidence and for organisations to provide access to materials, equipment, and records that it considers necessary for an investigation. The Health and Care Bill currently passing through parliament would provide them with these powers, as part of plans to convert the regulator into a new statutory organisation, the Health Service Safety Investigations Body.[3]

In response to the failure of the community pharmacy to engage with the investigation, HSIB made the following safety observation:

“It may be beneficial if professional bodies provided guidance and further support to their members to maximise the learning that can be achieved from safety investigations that may improve patient care.”

We believe there is a need for a stronger and more specific action in response to this. Professional bodies and regulators, such as the Royal Pharmaceutical Society and General Pharmaceutical Council, make it clear that defensive and closed cultures in organisations are not acceptable.[4] [5] We consider that such behaviours must be identified and addressed.

Yellow Card scheme

In our recent Mind the implementation gap report, one of the areas where we identified a significant gap between what we know about patient safety and what is done in practice was incident reporting.[6] When discussing this we specifically mentioned the Medicines and Healthcare products Regulatory Agency (MHRA) Yellow Card scheme. This is a system for voluntary reporting of safety issues concerning medicines and medical devices by the public and healthcare professionals.

HSIB noted the following regarding the Yellow Card scheme in this case:

“The investigation was told by the Trust that a Yellow Card report should have been submitted in Len’s case. However, it had not happened. The investigation was told that when staff were under great pressure Yellow Card reports did not always get submitted and that side effects related to respiratory issues from morphine sulfate were already recognised.”

The shortcomings of the Yellow Card scheme in effectively identifying medication and safety issues have been well documented, particularly by the Independent Medicines and Medical Devices Safety (IMMDS) Review published in 2020.[7] In light of this, the Government and MHRA have committed to take steps to improve the scheme.

This case illustrates the one of the challenges of ensuring that the Yellow Card scheme is used effectively and that the importance of routinely recording and reporting these types of incidents is embedded throughout the healthcare system. This is an area where we feel an additional safety recommendation could have been added to this report.

Patient engagement

Patient engagement is key to improving patient safety. In our report, A Blueprint for Action, we identify this as one of the six foundations of safe care.[8] We believe that patients should be engaged for safety at the point of care, if things go wrong, in improving services, advocating for changes and in holding the system to account.

In this case gaps in information hinder our understanding of how Len and his Wife were communicated with during the prescription of morphine sulfate. HSIB stated that they were unable interview the GP, therefore the only information on this was taken from Len’s medical notes. It is not known what advice was given on how to take the morphine sulfate. Due to the lack of cooperation by the community pharmacy, there is also an information gap about what dispensing advice was given.

The report does note another factor that may have impacted on the communication of advice on the dosage, stating:

“Len’s Wife was recovering from surgery on her ears for an existing hearing problem and had some known memory problems. When taken together with the passage of time since she collected the prescription, the investigation cannot be certain whether any advice given could have been heard, and if it was heard, whether Len’s Wife now remembers it.”

Patients and carers need to be assured that medication prescription processes involve clear communication and account for any barriers to this. Unsafe medication practices and medication errors are a leading cause of avoidable harm and are the focus of this year’s forthcoming World Patient Safety Day in September.[9] There is a wealth of existing research and good practice on this, including the World Health Organization’s 5 Moments for Medication Safety campaign, which highlights to patient and carers the key moments where action by the healthcare professional, patient or carer can greatly reduce the risk of harm associated with the use of medications.[10]

With significant gaps in information, it is difficult to make any firm recommendations stemming from this specific case, however this does point towards the wider work that is needed to improve medication safety.

Safety concerns about liquid morphine

Patient safety concerns relating to the risk of unintentional overdoses involving liquid morphine have also been raised beyond this specific case. Last year research conducted by the Pharmaceutical Journal revealed that liquid morphine contributed to the cause of death in Coroner’s Prevention of Future of Deaths reports in the cases of at least three men and ten women since 2013.[11] In three of these cases, the coroner’s recommendations appealed for healthcare bodies and government departments to put in place additional restrictions on the prescription of morphine sulfate. This research highlighted some themes in common with the HSIB investigation around unintentional overdoses and questions around the guidance provided when this was being prescribed.[12]

Concerns about patient safety incidents associated with morphine sulfate have also been raised previously in Controlled Drugs Newsletters in the NHS in the North Midlands and South West Midlands NHS in 2016.[13] [14] This has also been raised more recently in a Care Quality Commission Controlled Drugs Newsletter, published in April 2021, which stated that there “is significant under-reporting of incidents with this medicine to Controlled Drugs Accountable Officers”.[15]

We believe that may be a need for a further investigation of this patient safety issue by NHS England and NHS Improvement.


[1] HSIB, Unintentional overdose of morphine sulfate oral solution, 28 April 2022.

[2] Patient Safety Learning, Mind the implementation gap: The persistence of avoidable harm in the NHS, 7 April 2022.

[3] Department of Health and Social Care, Health and Care Bill: Health Services Safety Investigations Body, Last Updated 10 March 2022.

[4] Royal Pharmaceutical Society, Professional standards for the reporting, learning, sharing, taking action and review of incidents, November 2016.

[5] General Pharmaceutical Council, Standards for registered pharmacies, Revised June 2018.

[6] Patient Safety Learning, Mind the implementation gap: The persistence of avoidable harm in the NHS, 7 April 2022.

[7] The Independent Medicines and Medical Devices Safety Review, First Do No Harm, 8 July 2020.

[8] Patient Safety Learning, The Patient-Safe Future: A Blueprint For Action, 2019.

[9] World Health Organization, World Patient Safety Day 2022, Last Accessed 27 April 2022.

[10] World Health Organization, 5 moments for medication safety, 1 July 2019.

[11] Carolyn Wickware, Government fails to respond to calls for tighter controls after liquid morphine deaths, The Pharmaceutical Journal, 2 September 2021.

[12] Carolyne Wickware, Investigation: should liquid morphine be reclassified?, 2 September 2021.

[13] NHS England, North Midlands Controlled Drugs Newsletter, December 2016.

[14] NHS England, Controlled Drugs Newsletter: Sharing Good Practice in the South West, August 2016.

[15] Care Quality Commission, CQC’s Controlled Drugs National Group Newsletter, 10 April 2021.

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