Pharmacogenomics in prescribing: building competence for safer, personalised care
Published: 18 March 2026
This was published when the organisation was the Royal Pharmaceutical Society.
Pharmacogenomics — the study of how a person’s genetic makeup affects their response to medicines — is becoming increasingly relevant to prescribing practice. As genomic medicine develops across the UK, prescribers need the confidence to recognise when genetic factors may affect treatment decisions, medicine efficacy or the risk of adverse drug reactions.
The Royal Pharmaceutical Society’s (RPS) Pharmacogenomic Resource to Support the Competency Framework for All Prescribers is designed to support prescribers of all professional backgrounds in this evolving area of practice. Sitting alongside the RPS Competency Framework for All Prescribers, it provides structured guidance to help integrate pharmacogenomic principles into everyday prescribing practice safely and responsibly.
Why pharmacogenomics matters for prescribers
Genetic variations between people can affect how their bodies handle medicines. These differences can influence how quickly or slowly certain medicines are broken down, how well the medicine works and the risk of side effects. In certain clinical scenarios, pharmacogenomic testing can help inform medicine choice or dose selection.
For prescribers, competence in pharmacogenomics does not require specialist training in genomics. Rather, it involves:
- Recognising when genetic factors may be clinically relevant
- Understanding how to interpret validated information appropriately
- Applying that information alongside clinical judgement
- Incorporating insights into shared decision-making with patients
Pharmacogenomics aids professional clinical judgement by providing additional evidence to inform prescribing decisions, supporting medicines optimisation and improving patient safety.
Supporting confident implementation across the UK
The RPS Pharmacogenomic Resource is designed for prescribers at all stages of their careers, from those developing their prescribing practice to experienced prescribers expanding their scope.
It reflects the realities of implementation across the UK, including differences in access to pharmacogenomic testing and local service provision. By looking at prescribers’ competencies through a pharmacogenomic lens, the resource supports safe and accountable practice across care settings when pharmacogenomic testing is used.
The need for prescribers to have clear communication with patients remains central. Discussions about genetic testing and treatment options must be handled sensitively, with consideration of cultural and ancestral factors where appropriate. Accurate documentation and information sharing are essential to support continuity of care, particularly as genetic results remain constant even though interpretation may evolve over time.
Looking ahead
Pharmacogenomics is likely to become an increasingly integrated component of prescribing practice in the coming years. By using this resource, prescribers can ensure they are equipped to adapt safely as the use of personalised medicine continues to develop.
By strengthening the understanding of pharmacogenomics within existing prescribing competencies, this resource supports safer, more personalised and evidence-based care.
Explore the RPS Pharmacogenomic Resource to Support the Competency Framework for All Prescribers and learn more about building your competence in pharmacogenomics.
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On track for royal college
This article was published when the organisation was the Royal Pharmaceutical Society. This is my second blog with updates on our work to become ‘royal college-ready’. My last blog followed closely after an Assembly meeting at which details were discussed about the shape of the royal college and how it would be governed. This time I’m writing just ahead of a meeting where Assembly members will be fleshing out the final details on, among other issues, our inaugural royal college elections. What I hope this indicates is the progress we’ve made over the summer on developing the shape and structure of the new organisation. This ongoing work is taking place on a few different fronts. The first I’d like to talk about is appointments – of key roles within the staff, of expertise to the new Board of Trustees, and of our first cohort of elected members to the royal college and the new structures they will operate within. I was delighted last week to announce our new Chief Scientist, Professor Amira Guirguis, which followed the announcement in September of a new Director for Wales, Dr Geraldine McCaffrey who begins in her role in December. These hires show how we are ensuring we remain focused on our work across the nations and in areas of practice and research that are vital to the role we will play as a royal college. We are in the process of recruiting new Directors of Education, Pharmacy, Finance and Technology, and we have asked our Director of People to lead on our Shared Services portfolio, which will form a crucial link between the Royal College of Pharmacy charity and the subsidiary business, Pharmaceutical Press. We will announce our new appointments as they are filled and look forward to bringing the new team members on board. A vital aspect of our new governance is the creation of a Board of Trustees for the charity. This body ensures we have appropriate oversight and remain focused on our mission and charitable aims. It’s exciting to have begun our search for a ‘founding’ Chair of Trustees to lead this important work. We’re working with specialist recruiters Charity People to secure the right candidate. Sitting alongside the Board of Trustees in the governance structure will be the Senate and three national councils. Assembly will be discussing the elections process in detail when they meet this week. There will be much more to say on the elections as they approach and it’s something I will report on further. Ahead of this, however, is the task of putting in place the Regulations for the new organisation. We intend for this to be undertaken in two phases. In the first, we will publish the draft interim transition Regulations to enable elections to the new royal college structure and transfer the Pharmaceutical Press into a subsidiary company. In the second phase we will publish the draft full Regulations for the Royal College of Pharmacy, which will sit alongside the proposed new Royal Charter. We will be engaging with RPS members on these draft Regulations through the autumn and will share more detail after Assembly have met this week. All this activity puts in place the structures we need to deliver our future strategy as the Royal College of Pharmacy. The development of that strategy has been the third strand of work in preparing for our royal college transition, and a key focus of the last couple of months. I’m delighted that our first two online events, with pharmaceutical scientists and pharmacists working in industry, followed closely by a session with RPS members, were well attended and positive. The President and I also had the opportunity to join our Retired Pharmacist Group at their recent meeting and we know there is also a lot of interest amongst retired members in participating in the building of the new strategy. I’m grateful to everyone that has taken the time to contribute and support this work so far. We’re also holding a members and non-members online event on 23 October, and a student event, co-hosted with the BPSA, on 4 November. Your ideas will help shape the strategy of the new royal college, so I’d encourage anyone who hasn’t yet to sign up for one of our last two sessions. RPS members can also share their views via an all-member survey (now closed). This process of listening and engaging means our strategy development process is inclusive of the whole of pharmacy – vital for ensuring it serves the whole profession. We are building the strategy on our five commitments, as well as our pledge to RPS members about the kind of service we will provide throughout individuals’ careers. Patient safety will run as a ‘golden thread’ through all parts of the strategy. Meanwhile there’s plenty of other important activity that I might call ‘business as usual’. A particular highlight to mention is last week’s workforce summit, which took forward our work on assessment and credentialing. The focus for the meeting was developing and implementing an enhanced curriculum for newly qualified pharmacists, all of whom will be prescribers from next summer. The advent of all new pharmacists being independent prescribers represents a massive shift in healthcare – underlining again the importance of creating the Royal College of Pharmacy. In the context of seismic change to the pharmacy professions and healthcare as a whole, pharmacy needs a strong, unified voice, and professionals need support throughout their careers. It’s an excellent reminder of why the work to get ‘royal college ready’ is so important.
Revisiting the Peppermint Water case: what would happen now?
This was published when the organisation was the Royal Pharmaceutical Society. Simon Perkins is a medical malpractice specialist and leads DACB's national medical-malpractice group. He has over 20 years' experience of defending clinical negligence claims, in a wide variety of specialisms, and is respected for his commercial advice and insurance law expertise. He is also directly instructed by healthcare providers to advise on risk management, early response to critical incidents and is sought out to manage group actions. Simon manages the national medical-malpractice group from Bristol. After starting his career in community pharmacy, Neal Patel joined the Royal College of Pharmacy in 2009 from the National Pharmacy Association, where he first managed NHS engagement and latterly headed up communications. As head of corporate communications, Neal was the organisation's main spokesperson, regularly appearing on the BBC, ITV, Channel 4 and digital media outlets. Neal was appointed to associate director of membership in 2023, supporting pharmacists and pharmaceutical scientists with impactful services, insights and a sense of belonging — enhancing their practice, raising the College’s profile, and advancing patient care. Neal remains a registered pharmacist and is trustee of the charity the Association of Young People’s Health. Many pharmacists will have heard about the “Peppermint Water” case. It is an unusual and tragic case from 1998 that remains a sobering example of how a single dispensing error can have devastating consequences. Decades on, both the legal framework around inadvertent dispensing errors and the indemnity protection available to pharmacists have changed significantly. This blog revisits the case, exploring how modern laws, statutory defences and RPS Professional Liability Insurance would apply if such an error occurred today. The Peppermint Water case In this case, a baby, just four days old, was prescribed peppermint water from a pharmacy to treat colic. Due to a dispensing error, he was given double‑strength chloroform water instead of the correct, diluted preparation and suffered a fatal cardiac arrest. Both the pharmacist and the pre‑registration trainee involved were criminally charged with gross negligence manslaughter. They were ultimately cleared of manslaughter but fined £1,000 and £750 under section 64 of the Medicines Act 1968 for supplying a medicinal product not of the nature and quality specified. While much of the professional discussion focuses on the legal position and the insurance response, it is crucial not to lose sight of the human impact. The parents, extended family and friends will have been profoundly affected by the loss of a child so young. That loss sits at the heart of this case and should remain at the forefront of our minds when we talk about it today. If an inadvertent error like this occurred today, the legal position for pharmacists would be very different. As would the insurance support that is now available to. The criminal law around dispensing errors Pharmacists often worry about the risk of criminal prosecution if something goes wrong. There is concern that an inadvertent error might lead to life-changing legal consequences. The starting point is that prosecutions of healthcare professionals for gross negligence manslaughter remain rare. The threshold is high: behaviour has to be “criminally reprehensible”, not simply a mistake. However, sections 63 and 64 of the Medicines Act 1968 make it an offence to adulterate or sell any medicinal product which is not of the nature or quality demanded. These offences can carry sentences of up to two years' imprisonment. Historically, this contributed to a culture of fear, in which mistakes were sometimes concealed, as pharmacists were understandably concerned about the risk of prosecution. The 2018 reforms: a statutory defence for inadvertent dispensing errors A major shift came after a government consultation in 2018, influenced heavily by campaigning from the RPS and others. The Pharmacy (Preparation and Dispensing Errors – Registered Pharmacies) Order 2018 introduced a new statutory defence for inadvertent dispensing errors in registered pharmacies. To rely on this defence the individual must: be a registered pharmacy professional (or working under their supervision) be working in a registered premises in the course of their professional duties be following the directions of a prescriber or dispensing as per a prescription not have known at the time of sale or supply that the product was adulterated or not of the quality required. Crucially, once the individual becomes aware of the error, they must take all reasonable steps to promptly notify the person for whom the product was intended. That emphasis on prompt, open reporting is central. The defence is designed to protect pharmacists who make inadvertent errors but then do the right thing. Extending protection beyond community pharmacy When first introduced, these protections applied only to registered community pharmacies. This left a gap for hospital and other pharmacy services. Following further lobbying from the RPS, The Pharmacy (Preparation and Dispensing Errors – Hospital and Other Pharmacy Services) Order 2022 was introduced, which extended the same protections to hospitals and other regulated settings. Today, provided the statutory conditions are met and the error is promptly reported, pharmacists in both community and hospital settings have access to these defences. The intention is to support a more open, learning culture around inadvertent dispensing errors, making prescribing safer. If something similar happened today: how would RPS Professional Liability Insurance help? Alongside the legal framework, pharmacists need to understand how their professional liability insurance can help if the worst happens. If a modern-day equivalent of the Peppermint Water case occurred, what support and protection would be available to an employed pharmacist who has RPS Professional Liability Insurance? RPS Professional Liability Insurance can support in three key ways, assuming the RPS member had notified the insurer correctly: Criminal Investigation: If the police open a criminal investigation, the policy can cover legal representation and defence costs for the RPS member Having specialist legal advice and support at this stage can be critical, both for navigating interviews under caution and for understanding how the investigation might progress. Regulatory Investigation: If the GPhC open an investigation or refer the matter to a Statutory Committee, the insurance can cover the legal representation costs for the RPS member in those proceedings. Regulatory processes can be lengthy and complex; having expert support helps ensure the pharmacist’s position is properly explained and that learning, remediation and insight are clearly demonstrated. Civil claim for compensation: If a patient or their family brings a civil claim for damages e.g. compensation for harm caused by a prescribing error, then the employed pharmacist would either have cover through their employer, or if no cover was available, would have cover through their RPS Professional Liability Insurance. This safety net is called "contingent cover". Understanding Contingent cover Contingent cover is an area that is not always well understood, but it is a key part of the protection available to employed pharmacists. For employees, the principle of “vicarious liability” means that the employer is normally the one who carries legal responsibility for acts or omissions that occur in the course of employment. Any civil claim for compensation is therefore usually directed at the employer, and the employer’s insurance policy responds in full. Whilst the expectation is that an employed pharmacist will therefore benefit from coverage for any claim under their employer's liability policy, contingent cover acts as a back-up. If, in a particular case, the employer’s policy does not or cannot respond –RPS Professional Liability Insurance can then respond for the individual pharmacist. It is important to emphasise that this contingent element of the policy: Applies only to civil claims for damages (for example, compensation claims following a dispensing error); and Applies only to employed pharmacists, because they are the ones who would normally expect their employer’s policy to respond first. Why avoid “dual indemnity”? Another reason for structuring cover in this way is to avoid “dual indemnity” or double cover. Pharmacists may have cover under both an employer’s policy and a personal policy but if both simultaneously attempt to respond fully to the same civil claim, then disputes can arise between insurers over who should pay, and in what proportion. This can cause delay, increase legal costs, and add to the stress for the pharmacist involved. The contingent model aims to give employed pharmacists the security that they will not be left exposed if an employer’s policy fails, while reducing unnecessary costs, overlap and arguments between insurers. Support even when the claim is only against the employer In the situation where a claim is brought against the pharmacist’s employer rather than the individual, the pharmacist would not be left to face the situation alone. For example, they could call the medicolegal helpline for support to: Obtain guidance on ensuring the claim is properly treated as the employer’s responsibility under vicarious liability; or Seek independent advice if they are uncomfortable with how the employer or its insurers are handling the matter. Self‑employed and locum pharmacists: primary cover The position is different for self-employed and locum pharmacists. In these scenarios, there is no employer in the same sense, and therefore no organisation standing behind them to carry vicarious liability in the usual way. For self-employed and locum pharmacists: The cover under RPS Professional Liability Insurance is not contingent – it is primary. If a civil claim for damages is brought directly against them, their RPS policy is designed to respond in full, subject to the policy’s usual terms, conditions and limits. The same broad types of support apply – civil claims, criminal investigations and regulatory proceedings – but without the assumption that an employer’s policy will go first. This makes it particularly important for self-employed and locum pharmacists to ensure they maintain robust personal indemnity arrangements. Key takeaways from the Peppermint Water case today Reflecting on the case in the current landscape, several key messages stand out. When Contingent cover applies: Employed pharmacists can normally expect their employer’s insurance to respond to civil claims for damages, with RPS contingent cover stepping in only if the employer’s cover does not provide cover. Self-employed pharmacists cannot rely on an employer’s policy and must ensure they have appropriate personal indemnity in place. For this reason, the cover for self-employed pharmacists under the RPS Professional Liability Insurance is NOT contingent. They would be covered for any claims for damages made against them directly. Regulatory Investigations – All pharmacists, whether employed or self-employed, can access support around criminal and regulatory investigations through RPS Professional Liability Insurance. This is not contingent. Reporting dispensing errors: Inadvertent dispensing errors should be reported promptly. This legal and insurance framework supports a safer, more open culture where pharmacists can learn from errors. It is also a requirement for pharmacists to benefit from the new statutory defence. The Peppermint Water case is a stark reminder of the potential consequences of an error. If it arose today as an inadvertent dispensing error and was reported promptly, it would be far less likely to result in criminal sanctions for the pharmacist involved. Pharmacists must still ensure they have adequate personal indemnity in place for all their work – for employed staff through their employer and contingent cover but for self-employed / locum pharmacists through full personal indemnity. Understanding how the law and indemnity landscape have evolved helps ensure pharmacists feel supported, protected and able to practise in a transparent, learning‑focused environment. The profession has come a long way in creating a more just, learning focused environment that prioritises patient safety since the tragedy of 1998. More information on RPS Professional Liability Insurance RCPharm Professional Liability Insurance is arranged by Aon UK Limited and underwritten by certain Underwriters at Lloyd’s led by Carbon Syndicate 4747. Aon UK Limited is authorised and regulated by the Financial Conduct Authority. Registered in England and Wales. Registered number: 00210725. Registered Office: The Aon Centre, The Leadenhall Building, 122 Leadenhall Street, London EC3V 4AN. Registered head office tel: 020 7623 5500 – NB. this number is for general enquiries only; if you have a question about the RPS Professional Liability Insurance policy, please call the RPS membership team on 0207 572 2737 or refer to www.rcpharm.org/insurance. The following products or services provided by Aon UK Limited are not regulated by the Financial Conduct Authority: Legal advice and defence services Medico legal helpline FP.CORP.2026.46