Medication errors and how to avoid them 

Medication errors are a common cause of harm. Dr Clare Sweeney examines the risks and how they can be mitigated 

Every year, tens of millions of drugs are prescribed, dispensed, and administered to patients, helping to ease their symptoms and support their recovery. But errors can creep into the process, with the potential to cause serious harm.

The following fictional scenario shows what can go wrong:

A consultant saw an outpatient with poorly controlled hypertension. The patient said she was not on any other medication, but did not mention that she was regularly taking over-the-counter ibuprofen for back pain. The consultant recommended an ACE inhibitor and explained what to do in the event of side-effects.

When the patient fell ill with gastroenteritis, she continued to take the ACE inhibitor and was later admitted to hospital, where she was found to be suffering from acute kidney injury which required long-term dialysis. She made a claim alleging the consultant should have checked whether she was taking other medications and warned her about the risks of taking NSAIDs and becoming dehydrated. 

The scale of the problem

HIQA has calculated that there may be around three million medication errors per year in Irish public hospitals based on an earlier estimate by the Institute of Medicine (United States).

A number of national initiatives have been launched to tackle the issue, including the Safermeds campaign by the HSE’s Quality and Patient Safety division. The Irish Medication Safety Network also issues regular safety alerts following reported incidents and has published Building a Medication Safety Programme in Acute Care in Ireland – Fundamental Steps.

Medication errors are a worldwide problem with the World Health Organisation (WHO) reporting that harm due to medicines and therapeutic options accounts for nearly 50 per cent of preventable harm in medical care. It has made ‘medication without harm’ a global patient safety challenge. The WHO’s 2024 progress report identified three priority areas: High-risk situations, polypharmacy, and transitions of care.

Reducing medication risk

You are responsible for all the prescriptions you sign so it is important to know how to be a safe prescriber. Here are the Medical Defence Union’s (MDU) top tips.

1. Understand common risk factors

In the MDU’s experience, the most common medication errors are:

▶ Prescribing to someone with a known allergy, especially penicillin.

▶ The wrong drug. This can happen with sound-alike and look-alike drugs or when selecting from drop-down menus. For example, penicillamine instead of penicillin or Depo-Medrone instead of Depo-Provera.

▶ The wrong dose. Confusion about the strength (eg, opioids), different formulations of the same drug, frequency (eg, methotrexate), or miscalculating a dose based on body weight.

▶ Failing to consider drug interactions. For example, a patient on anti-epilepsy medication becomes pregnant.

▶ Failing to monitor patients on long-term medication. As in the case example above, renal function monitoring for patients on ACE inhibitors.

Other high-risk situations include treating frail or very young patients, using high-risk drugs, unlicensed medicines (especially in paediatrics, psychiatry, and palliative care), remote prescribing, and shared care arrangements with the patient’s GP.

2. Communicate effectively with patients

A two-way dialogue will help you take an accurate and complete history (including current medications), obtain informed consent, and provide clear safety netting advice, including:

▶ How and when to take the medication.

▶ How to adjust the dose if necessary.

▶ Likely duration of treatment.

▶ Arrangements for monitoring, follow-up, and review.

▶ What to do if the patient experiences side-effects or a recurrence of their condition.

Engaging with patients is central to the HSE’s Know, Check, Ask campaign, which recommends that healthcare workers encourage people on medication to keep an up-to-date list of their medicines and ask whether they have this with them during an appointment.

3. Ensure records are updated

To ensure continuity of care, prescriptions should be carefully documented in the patient’s clinical notes, along with the name of the prescribing doctor and relevant details such as allergies, adverse reactions, and poor tolerance of a particular drug.

When patients are discharged, the Medical Council’s Guide to Professional Conduct and Ethics for Registered Medical Practitioners (9th edition) says this “must be accompanied by a timely and prompt discharge summary which includes at least the minimum basic information” including medication and medication changes (paragraph 33.7).

The WHO’s 2024 progress report identified three priority areas: High-risk situations, polypharmacy, and transitions of care

4. Check monitoring arrangements

Pay special attention to high-risk drugs that have been commenced during admission and arrange for newly prescribed medicines to be reviewed within a defined period. A hospital stay is also a good opportunity to review patients’ existing medication to ensure it is clinically appropriate and whether they are experiencing any side-effects or there is a risk of dependency.

5. Keep on top of guidance and procedures

Follow your hospital’s prescribing protocols and patient safety systems and refer to authoritative guidance such as the Irish Medicines Formulary. The Medical Council’s ethical guide covers prescribing and prescribing controlled drugs (paragraphs 34 and 35) and it has published joint guidance on the safe prescribing and dispensing of controlled drugs with the Pharmaceutical Society of Ireland.

6. Respond appropriately to errors and adverse reactions

If you identify a prescribing error, give the patient an open and honest explanation of what has happened, apologise, and reassure them of the steps you are taking to put things right (seeking specialist advice if needed).

The Medical Council expects doctors to comply with safety procedures which includes reporting incidents (via the National Incident Management System), learning from them, and taking part in any subsequent review. Seek advice from your hospital in the event of a medication incident leading to the death of a patient as these are now notifiable under the Patient Safety (Notifiable Incidents and Open Disclosure) Act 2023, which came into effect in September 2024 (see the HSE’s website for information and resources for staff). 

Finally, report adverse drug reactions to the Health Products Regulatory Authority using its online form.

MDU membership gives State-indemnified doctors access to expert guidance with medico-legal dilemmas like prescribing concerns. We can support you with patient complaints, Medical Council investigations, inquests, and criminal matters.

To find out more see www.themdu.com/ireland