Supplementary prescribing is one of two models of non-medical prescribing (NMP) currently used in the UK, the other being independent prescribing. NMP describes prescribing that is undertaken by healthcare professions other than doctors or dentists. Completion of a recognised qualification is required to allow a healthcare professional to work with the additional responsibility. In the UK, the NMP workforce comprises nurses, pharmacists, and other allied health professionals (AHPs) (Beckwith and Franklin, 2011).
NMP began in 1992, with nurses, but since then it has evolved to incorporate a wider group of healthcare professions. The scope of practice has become more autonomous, allowing many of the early NMP healthcare professions to progress from supplementary prescribing to independent prescribing, as NMP has become more embedded in healthcare culture. Consequently, independent prescribing is the predominant model in the 2020s (Cope et al, 2016).
Legislation governs NMP within The Human Medicines Regulations (legislation.gov.uk, 2012). Changes to NMP require public consultations to support proposals made to the Commissions on Human Medicines before any amendments are agreed upon (Graham-Clarke et al, 2019). This is historically a lengthy process.
Dietitians and paramedics are the newest healthcare professions to begin NMP, many years since the last addition. Dietitians can work as supplementary prescribers (SPs), which is aligned with how other healthcare professions began NMP. However, paramedics have been permitted to work as independent prescribers (IPs) at the outset. While this may have set a precedent, the circumstances of their clinical field make a compelling argument in support of this.
NMP in the 2020s is fundamentally different to when supplementary prescribing was first introduced in 2003, when it was an unknown entity. As independent prescribing is now well-evidenced and established in healthcare, it is important to question whether new professions becoming non-medical prescribers need to begin with supplementary prescribing.
This paper will describe the models of NMP, outline how NMP has evolved and evaluate the current models in use, to enable discussion on the value of supplementary prescribing for dietitians in the 2020s.
Models of prescribing
Supplementary prescribing involves a voluntary partnership between an IP (a doctor or dentist) and an SP to implement an agreed, patient-specific clinical management plan (CMP), with the patient's agreement. Within this partnership, the IP is responsible for making the diagnosis, indicating which medications can be prescribed within the CMP, setting the parameters for its use and monitoring (Beckwith and Franklin, 2011).
The SP is responsible and accountable for their prescribing practice within the limits of the agreed CMP, which is the foundation of supplementary prescribing and provides the legal framework. It can be used to prescribe licensed medicines, unlicensed medicines or mixed medicines, but the SP will be limited to the medications indicated in the CMP. Any issues that arise need to be referred back to the IP (Department of Health, 2005).
In contrast, independent prescribing allows the practitioner to prescribe independently without any direct supervision. This involves making their own assessments and diagnosis to inform their prescribing decisions and they can prescribe any medication that is within their clinical competence (Beckwith and Franklin, 2011). Those working as IPs are still able to use the SP model, but for many, their independent prescribing rights has diminished the need. The ability to prescribe controlled drugs (CDs) varies between professions and is not automatic to IPs. Therefore, some IPs may use the supplementary prescribing model to be able to prescribe medications outside their permissions using a CMP.
Development of NMP
NMP was introduced in the UK in 1992, in response to the recognition that care could be enhanced if nurses were able to prescribe directly, rather than needing to seek prescriptions from doctors. Its purpose was to be more patient-centred and develop multidisciplinary teamworking (Beckwith and Franklin, 2011). Following many amendments to the scope of nurse prescribing, supplementary prescribing was introduced for nurses and pharmacists in 2003. This was a significant advance, as it permitted any medicines to be prescribed in comparison to the previous limited formulary (although limited to those indicated in the CMP) and opened up NMP to other professions. By the end of 2005, additional AHPs were permitted to work as SPs: physiotherapists, chiropodists, podiatrists, radiographers (diagnostic and therapeutic) and optometrists (Department of Health, 2005).
However, as a result of to the conditions of supplementary prescribing practice, scenarios quickly arose where the practicalities of partnership with a doctor became challenging. This was especially evident in more acute care environments or where the doctor and SP did not work in proximity. (Graham-Clarke et al, 2019). Consultation resulted in legislation changing in 2006, to permit nurses and pharmacists to prescribe independently. By 2012, all the other supplementary prescribing professions had progressed to independent prescribing, except for radiographers.
In 2016, dietitians were permitted SP status NHS England, 2016a) and therapeutic radiographers progressed to IPs within the same legislative change. A recent registrant snapshot in September 2021 showed that 161 dietitians had SP annotation on their registration: approximately 2% of registered dietitians.
More recently, paramedics have been granted independent prescribing rights without any prior NMP capabilities in response to recognition that their roles involve more urgent care, rendering SP status as impractical (College of Paramedics, 2018)
Evaluation of NMP models
Supplementary prescribing
As supplementary prescribing began with nurses and pharmacists, most understanding is derived from research of these healthcare professions.
A large survey undertaken in 2005 explored the prescribing practices of independent extended prescribers (a pre-2003 model) and SPs. It found that a majority were prescribing in primary care (82%), independent extended prescribing was undertaken more than supplementary prescribing (87% v 35%) and the three conditions most frequently prescribed for using the supplementary prescribing model were asthma, diabetes and hypertension. Factors most likely to prevent prescribing were inadequate formulary, for those working as independent extended prescribers, and implementation of the CMP (Courtenay et al, 2007).
While supplementary prescribing was considered to benefit from the safe framework that the CMP provided, it was noted that the CMP led to inflexible prescribing because of its restrictive nature. Furthermore, it did not acknowledge the complexity of some patients with multiple comorbidities and was not a holistic approach to patient care. It was suggested that moving toward independent prescribing would be more flexible, but that supplementary prescribing may still have a role as an introductory model for those without experience, to build confidence (Cooper et al, 2008)
A qualitative study exploring pharmacists' views before and after implementation of supplementary prescribing highlighted the anticipation of what the new role would involve. They felt that it would supersede the advisory role to doctors' prescribing decisions, by being able to undertake this themselves. Once implemented, many felt more involved and respected by their medical peers and that the risk of errors was minimised. However, the CMPs offset this positivity, as they were seen as cumbersome and timewasting (Tully et al, 2007). Nonetheless, a survey of UK pharmacist SPs indicated that they were confident in their extended role and felt it contributed to job satisfaction. They perceived that their patients were satisfied with their care and benefitted from better therapeutic management (George et al, 2007).
A mixed-methods study evaluating both nurse and pharmacist supplementary prescribing found it was difficult to implement, given the unwieldy use of CMPs, difficult access to medical records and information technology, as well as lack of funding for SP training. In terms of prescribing practice, SPs felt confident and competent to prescribe safely and this was supported by feedback from doctors. Patients indicated positive experiences of nurse and pharmacist SPs, considering them easier to talk to compared with doctors and their consultations were longer. They did not understand either the concept of supplementary prescribing or CMPs (Bissell et al, 2008). A further study indicated that the practical difficulties identified resulted in delays to SPs taking their new role forward once trained (George et al, 2006).
The smallest body of evidence arises from patient perspectives, which is disappointing given that NMP was designed to improve patient care. Patient perspectives contributed to a wider study exploring experiences of mental health nurse supplementary prescribing. Of the 11 patients interviewed, 10 found nurse prescribing to be person-centred, incorporating information giving, partnership working, offering choice and minimising risks, and felt it to be a positive experience overall. Additionally, more than half reported that the nurse prescriber provided more detailed explanations than the psychiatrists and gave more choice on treatment options (Jones et al, 2007).
Patients attending a pharmacist SP-led hypertension clinic were surveyed to explore a perceived positive response. Of the patients, 57% felt their care was better than previously and a further 32% found it comparable. 86% felt their understanding of their condition had improved since attending the clinic and felt more involved in treatment decisions. 86% indicated it was easier to make appointments, supporting the government's aim to improve access to medicines. However, appointment times in this clinic were purposefully set at 20 minutes rather than the standard 10 minutes to allow a prescribing partnership to develop. This may have been a key factor in its success (Smalley, 2006).
A patient survey in Scotland found high satisfaction with their consultations with pharmacist SPs and the medication information they were provided with. They trusted the SP and felt comfortable during their consultations. However, many still indicated they would prefer to see a doctor. It was suggested that this may have been related to long-established confidence in their doctors' support of their chronic conditions rather than there being specific issues associated with the pharmacist SP. This survey was conducted early in terms of pharmacist prescribing, so the practice was not widely established (Stewart et al, 2008).
Independent prescribing
The research literature on independent prescribing is far more comprehensive and includes evidence of its impact on outcomes. Nonetheless, limited research has been conducted in professions other than nurses and pharmacists (Cope et al, 2016).
An evaluation of nurse and pharmacist IPs indicated that most were using their qualification (93% of nurses and 80% of pharmacists), largely driven by the individuals themselves rather than a redesign of services (Latter et al, 2010). This contrasted with an earlier study of SPs, where only a small proportion of those trained were prescribing (28% of nurses and 51% of pharmacists); this was attributed to the cumbersome use of the CMP (Bissell et al, 2008). Additionally, independent prescribing was evaluated as being safe and clinically appropriate, highly acceptable to patients and most patients within the later study had no preference for either a doctor or NMP (Latter et al, 2010).
Patient perspectives often related to practical benefits, in addition to positive relationships with the prescribers. They indicated more flexibility with appointments, ease of access and were supplied with more relevant and comprehensive information (Courtenay et al, 2010; 2011; McCann et al, 2015; Tinelli et al, 2015). Strong relationships with the prescribers were described, related to establishing good rapport which had developed as a result of feeling listened to, promoting trust and openness (Stenner et al, 2011; Deslandes et al, 2015). These strong relationships had positive effects on shared decision-making, increasing confidence levels, which further impacted concordance and self-management (Courtenay et al, 2011; Deslandes et al, 2015; Ross, 2015; Stenner et al, 2011).
A 2016 Cochrane review examined NMP versus medical prescribing for acute and chronic disease management in primary and secondary care. Key findings suggested NMP was being undertaken in various settings, with comparable outcomes: management of systolic blood pressure, glycated haemoglobin, low-density lipoprotein, medication adherence, patient satisfaction and health-related quality of life. The findings supported NMP roles in the UK healthcare systems and workforce (Weeks et al, 2016).
In summary, independent prescribing has all the benefits associated with supplementary prescribing and has demonstrated that the close governance of the CMP is not necessary to support proficient prescribing practice.
Discussion
Dietitians joined the NMP community as SPs 24 years after nurses began prescribing. This has been a long-awaited development for the profession, acknowledging dietitians' capabilities, and has the potential to better meet patients' needs. Dietitians are in a unique position to prescribe medications that are dependent on food knowledge to maximise their efficiency, eg phosphate binders, pancreatic enzymes, insulin etc.
SPs undertake the same course as IPs, often learning alongside each other, so those qualifying at the end of the course have equivalent skills and knowledge to support their prescribing practice. It is solely the legislation, specific to individual healthcare professions, that governs the model with which they can work, and this difference is acknowledged in competency assessment on completion of training. If legislation changes in the future for SPs to be able to work as IPs, an additional conversion course will be required despite undertaking the same course initially, and will necessitate cost, additional competency assessment and further time commitment from the SP.
It is now common practice to be prescribed for by a healthcare professional other than a doctor and the benefits observed by patients are consistent and irrespective of the model of NMP used. Confidence in NMP has grown and its value has been extensively supported by research establishing it to be safe and clinically appropriate, acceptable to patients and has demonstrated non-inferiority to prescribing undertaken by doctors (Gielen et al, 2014; Weeks et al, 2016). Although currently unproven because of a lack of research, these benefits may also be observed with dietitian prescribing.
Dietitians who work as SPs tend to work within close multidisciplinary teams (MDTs) caring for people who have long-term conditions where diet and medication treatment strategies are interlinked: diabetes, chronic kidney disease, cystic fibrosis, inflammatory bowel disease and intestinal failure. Shifting the prescribing from a doctor to a dietitian has provided the potential to minimise duplication and avoid mixed messages for patients. Dietitians can now advise on diet and medication together, while relinquishing the additional direct involvement of the doctor. It has also allowed the dietitian to develop prescribing competency, which is invaluable.
In theory, the model of supplementary prescribing should be ideal for use within MDTs because of the close supervision required, however, for prescribing to be undertaken, a patient-specific CMP needs to be in place. It is not always clear before a dietetic consultation if medication changes will be required, as diet is often initially assessed to identify this. This may result in delays to prescribing if a doctor is not contactable to agree a CMP, as working closely within MDTs does not always necessitate working in the same location. This delay will not differ greatly from practice without supplementary prescribing ie liaising with a doctor once a prescribing need is identified, and changes are then made by the doctor.
At its inception in 2003, supplementary prescribing was considered quite radical, permitting healthcare professionals without traditional medical training to prescribe any medications, but it provided a pathway to delegate prescribing responsibilities within a safety net, and was appropriate for the healthcare climate at that time. However, the CMP, the underpinning regulatory document, can be a barrier to efficient supplementary prescribing in practice, as documented in studies from other clinical fields (Tully et al, 2007; Bissell et al, 2008). Doctors are not always immediately available to complete a CMP, delaying supplementary prescribing, an issue already shown to be prohibitive and associated with a reluctance to prescribe once trained (George et al, 2006; Courtenay et al, 2007).
This issue was also raised within a scoping project, which was undertaken to support the extension of prescribing and medicines supply by AHPs (Department of Health, 2009). It suggested that implementation difficulties arise when there is an incompatibility between necessary mechanisms and the needs of patients. The main issue being doctor availability for CMP agreements. In addition, the report highlighted that there are often situations when the AHP is the expert in a clinical condition/intervention, or the professional most familiar with the clinical case, yet the SP needs an IP to validate their expert opinion.
Both issues affect dietitian prescribing, where many of the relevant medications are dependent on food knowledge, and access to doctors cannot always be instantaneous. Reassuringly, once the CMP is in place and prescribing follows, patients are generally positive about their experiences with both SPs and IPs and the value of NMP is realised from this point forward (Smalley, 2006; Jones et al, 2007; Stewart et al, 2008; Courtenay et al, 2010; 2011; Deslandes et al, 2015; McCann et al, 2015; Tinelli et al, 2015).
In the 2020s, supplementary prescribing has been almost entirely replaced with independent prescribing for most of the NMP healthcare professions, bypassing the need for a CMP. Dietitians and diagnostic radiographers are the exception to this.
The radiography profession did put forward a proposal for IP status in 2016, however, it was only permitted for therapeutic radiographers as the diagnostic radiographers were not able to justify the need (NHS England, 2016b). Dietitians proposed supplementary prescribing as their initial step into NMP, as this is how all professions have begun and there was no precedent to do otherwise. This was despite difficulties with the model already being well-documented (Tully et al, 2007; Bissell et al, 2008). More recently, paramedics were able to justify the incompatibility of the SP model with how they work, and were granted IP status without prior NMP experience (College of Paramedics, 2021)
Considering that NMP was introduced to improve patient access to treatment and to make better use of resources, the supplementary prescribing model can be seen as potentially outdated in the 2020s. Although there appear to be no differences to how prescribing is perceived by patients, the practicalities of implementing the supplementary prescribing model cannot continue to be ignored. Discontinuing supplementary prescribing in favour of independent prescribing will not cease supervision between doctor and non-medical prescriber but will foster effective team working for more complex prescribing decisions.
Dietitians are already embedded within MDTs, providing the opportunity for case discussions, and so the need for the close supervision required to agree a CMP is becoming increasingly redundant. It would permit smoother and more timely prescribing in practice if it were no longer necessary. Plans are underway to propose changes to legislation to permit dietitians to work as IPs but without supporting evidence, the case will be difficult to make. Where healthcare professions have previously progressed to independent prescribing, the time taken for legislation to allow this to happen has been lengthy and success has been dependent on credible supporting information.
Of course, research to explore the role of dietitian SPs is necessary to determine need and provide momentum to this development for dietitians. However, many dietitians may now wait to see if independent prescribing becomes a reality for the profession before training: they are starting to understand the limitations of the supplementary prescribing model as described by colleagues. This will also avoid the need to undergo the additional training necessary to change from working as an SP to IP. As an unintended consequence of this, this may contribute to further delays in gathering robust evidence to support IP for the profession.
Conclusion
NMP is well established in current healthcare practice, however, the need for two models of NMP in the 2020s is now questionable. Supplementary prescribing has been a useful model of NMP to introduce the non-medical healthcare professions to prescribing practice and is evaluated positively by patients. However, the conditions of supplementary prescribing associated with the use of a CMP, still present the same challenges that were identified many years ago and can impact efficiencies and cause frustration. Most professions have progressed to independent prescribing as confidence and competence in NMP has been achieved, demonstrating that close supervision is not necessary. Independent prescribing for all non-medical prescribers may be the optimum model of future prescribing. Where the SP model is necessary to support prescribing of certain medicines not permitted within a professions IP status, alternative mechanisms may need to be developed. More debate is needed on the future of NMP and the best way forward for small professions to demonstrate clinical service needs in the context of prescribing.
Key Points
- Non-medical prescribing is well-established in the NHS and accepted by both patients and healthcare staff
- Two models exist in practice – supplementary prescribing and independent prescribing
- Dietitians and diagnostic radiographers are the only healthcare professions limited to supplementary prescribing although its framework can be used by IPs
- The CMP required for supplementary prescribing is cumbersome and may limit prescribing because of its restrictive governance
- Use of the supplementary prescribing model in the 2020s is becoming a debatable model of NMP.
CPD reflective questions
- What are the benefits of supplementary prescribing?
- What are the drawbacks of supplementary prescribing?
- Are both models of NMP necessary in the 2020s?