The perils of prescribing

Doctors face a number of challenges when prescribing: Sara Dawson explores some risk strategies and looks at a classic case of a drug name mix-up

Mr G, a 53-year-old migrant worker from Latvia, was a long-term sufferer of ulcerative colitis. One day, his worsening symptoms prompted him to visit his local GP, Dr Q. He explained to Dr Q that he had been feeling generally unwell for three days, with increasingly frequent bowel movements and “bloody diarrhoea”.

Dr Q referred Mr G as an emergency admission to the local hospital. At the hospital Mr G was seen and eventually discharged with a prescription of prednisolone and sulfasalazine.

A month later, Mr G attended his local GP practice for a fit note. He was reviewed by Dr F, who provided a prescription for “sulfadiazine tablets 500mgs one to be taken twice a day 56 tablets”. Mr G took his prescription to the local pharmacy, which made up the prescription as sulfasalazine tablets 500mgs “take two, three times per day”.

Later that year, Mr G was seen by Dr F again in relation to an insurance claim. Again, the same prescription was given and, again, the prescription was made up by the pharmacy. This time the correct dosage was written up, but this time with sulfadiazine.

A month later, Mr G saw Dr Q for follow-up. Dr Q became aware of the previous prescribing errors and informed Mr G that he was taking the incorrect medication and should, in fact, have been prescribed sulfasalazine.

Mr G alleged that Dr F negligently prescribed him an incorrect medication and an incorrect dose. He also alleged that he suffered from abdominal pain and diarrhoea until the error was corrected. Dr F was found to have been in breach of duty in prescribing sulfadiazine instead of sulfasalazine, and the claim was settled for a low sum, with liability being shared equally by the pharmacist and Dr F.

Although there was evidence Mr G suffered abdominal cramps and diarrhoea, he may well have suffered the same symptoms anyway, as he had ulcerative colitis. However, a well-known side effect of most drugs includes abdominal symptoms and bowel disturbance, so it would be difficult to defend the case on this basis.

Fraught with risk

Prescribing for patients is fraught with risk: doctors in both primary and secondary care can face major challenges in prescribing safely. The ageing population and the increasing complexity of highrisk medications, coupled with an already highly-pressured mix of patient juggling and time pressures, are increasing these challenges.

"It is absolutely essential to have all the information you need on the patient you are prescribing for; this will avoid contraindications and hazardous drug-to-drug combinations, and alert you to a history of allergy"

In 2012, Professor Tony Avery led a major GMC-funded study, The PRACtICe Study: Prevalence and Causes of Prescribing Errors in General Practice, in England. His team analysed a 2% random sample of patients’ records from 15 general practices across England.

Prescribing or monitoring errors were detected for one in eight patients, involving around one in 20 of all prescription items. The majority were of mild to moderate severity, with one in 550 items being associated with a severe error. Given this context it is essential for doctors to do everything they can to mitigate risk.

Keeping up-to-date

According to Professor Avery, it is absolutely essential to have all the information you need on the patient you are prescribing for; this will avoid contraindications and hazardous drug-to-drug combinations, and alert you to a history of allergy. He adds: “Access to up-to-date medical records is critical here, as well as having readily available sources of drug information (such as the BNF). Keeping your knowledge of therapeutics up-to-date can also help.”

Analytical thinking

Recognising our limitations as doctors and “to err is human” will make us more vigilant in checking that we have not made slips, lapses or mistakes, says Professor Avery. This requires using a type of thinking that is purposeful, conscious and analytical. For example, double-check a prescription before signing it off; don’t let it become an automatic process.

High-risk patients on high-risk drugs

High-risk patients are not only those with very serious illnesses, says Professor Avery, but also patients with multiple long-term conditions. These patients are at risk from the range of different medicines they take and have an increased likelihood of suffering drug-related harm, due to their comorbidities and frailty.

High-risk patients present us with particular challenges because considerable time is needed to manage all of their conditions, and prescribing safety can be overlooked. Professor Avery adds: “High-risk drugs include those that doctors prescribe in shared care arrangements between primary and secondary care, along with commonly used drugs such as warfarin, antiplatelet drugs, cardiovascular drugs, antiepileptics, psychotropics, opioid analgesics, diabetic drugs, systemic corticosteroids and NSAIDs.

“In high-risk patients it is essential to recognise that risks of serious medication-related harm may be considerably higher (possibly 100-fold higher) than in otherwise fit, healthy adults taking relatively safe medicines. We cannot afford to cut corners for our most vulnerable patients.”

Communication with patients

Communication problems often contribute to adverse events associated with medication errors, and are sometimes the main cause. The most common problems with communication occur between the doctor and patient, but there are also major issues at the interface between primary and secondary care.

Patients can and do suffer from medication-related adverse events because either they do not have sufficient knowledge of their medical conditions and the medicines they are taking, says Professor Avery, or they have not been given an adequate explanation of how to take the medicines, the side-effects to look out for and what monitoring is needed.

"Patients can and do suffer from medication-related adverse events because either they do not have sufficient knowledge of their medical conditions and the medicines they are taking"

Communication problems resulting in underuse, overuse or incorrect use of medication in general practice are particularly important in the following conditions where preventable drugrelated hospital admissions may result:

• asthma
• coronary heart disease with angina
• diabetes mellitus (especially in patients taking insulin)
• epilepsy
• heart failure.

For these conditions it is particularly important to try to make sure that patients have a good level of knowledge and understanding of their medicines. The use of patient information leaflets and websites may also be helpful.

Interface between primary and secondary care

It is not uncommon for patients to suffer medication-related harm as a result of inaccurate or incomplete information at the interface between primary and secondary care.

One very important issue is the danger associated with the transfer of medical information on to the practice computer once a patient has been discharged from hospital, or following outpatient visits. Unless this is done – or at least carefully checked – by clinically-trained staff, there are serious risks of inadvertent transcription errors or duplication of medicines.

Medication monitoring

According to Professor Avery, it is important to monitor patients for the effects of medications and any side-effects. Monitoring for side-effects is particularly important in older people, patients on multiple drugs, and patients with hepatic or renal impairment (where drug metabolism or excretion may be reduced, leading to drug toxicity).

"The evidence base for the benefits of medication monitoring is not strong for many drugs, particularly in terms of the frequency of monitoring"

Effective medication monitoring can help to identify problems before they result in serious patient harm. Nevertheless, the evidence base for the benefits of medication monitoring is not strong for many drugs, particularly in terms of the frequency of monitoring. Even so, it is important to have agreed policies for laboratory test monitoring of drugs, so that patients do not slip through the net and suffer from a complete lack of monitoring.

Even so, it is important to have agreed policies for laboratory test monitoring of drugs, so that patients do not slip through the net and suffer from a complete lack of monitoring. Advice on laboratory test monitoring is available from a number of sources, including the BNF and drug datasheets.

Medication review

It is important for patients’ medications to be reviewed periodically to ensure that essential laboratory tests are undertaken; side-effects are detected; patients are involved in decisions about their medicines; and therapy is optimised, says Professor Avery, although he notes that this can be challenging.

Controlled drugs

In August 2013, the Care Quality Commission (CQC) released its report, The safer management of controlled drugs: Annual Report 2012, which revealed a 1% rise in 2012 – compared to 2011 – in the number of prescriptions issued in primary care for controlled drugs.

Except for a steady fall in prescriptions of temazepam since 2007, the use of buprenorphine, morphine sulphate, oxycodone, fentanyl, midazolam and diamorphine is on the rise.

"Effective systems developed at the local level for secure gathering, sharing and recording of intelligence relating to concerns about safe management of controlled drugs should be preserved and transferred into the new NHS structure"

As a result, CQC chief executive David Behan called for “vigilance” around the prescription of controlled drugs – adding that the CQC would be including governance arrangements around controlled drugs as part of their inspections.

The recommendations of the report included:

• Health and social care professionals must ensure they know how to contact their local controlled drugs accountable officer (CDAO) and know the mechanism for reporting controlled drug concerns.
• CDAOs need to ensure they are following the guidance on the CQC’s website to update contact details promptly to ensure the CDAO register is accurate.
• Effective systems developed at the local level for secure gathering, sharing and recording of intelligence relating to concerns about safe management of controlled drugs should be preserved and transferred into the new NHS structure.
• CDAOs, clinical commissioning groups and controlled drugs leads must be mindful of their continuing responsibilities for good governance and safe use of controlled drugs to ensure ongoing monitoring and vigilance.

The importance of ongoing monitoring was underlined in a response to the report that was issued by NICE, specifically with regard to the use of drugs to treat moderate attention deficit hyperactivity disorder (ADHD).

Reiterating standards recommended in its recent quality standard on ADHD, a press release by NICE said: “The quality standard calls for people with ADHD who are taking drug treatment to be given a specialist review at least annually to assess their need for continued treatment… people taking the drugs need to be monitored regularly due to the number of side effects associated with drug treatment for ADHD, which can also have the effect of reducing adherence to treatment.

“Furthermore, without regular monitoring there is a greater risk that drugs prescribed to treat ADHD will be misused.”

Summary

In 2004 Sir Liam Donaldson said: “To err is human, to cover up is unforgiveable, and to fail to learn is inexcusable.” Errors are the product of multiple factors and clinicians have a duty to ward off error by employing defences to prevent it occurring in the first place. By being vigilant and making small changes medicines management can become safer.

Useful links

• GMC, University of Nottingham, The PRACtICe Study: Prevalence and causes of prescribing errors in general practice (May 2012)
• MPS factsheet, Safe prescribing (April 2013)
• CQC, Controlled Drugs – www.cqc.org.uk
• GMC, Good Practice in Prescribing and Managing Medicines and Devices (2013)
• National Institute of Health and Clinical Excellence – www.nice.org.uk
• MHRA – www.mhra.gov.uk

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