• Accreditation
• Adverse events, epidemiology and detection
• Ambulatory care

Adherence to medicines has been identified as a key issue by the Royal Pharmaceutical Society of Great Britain,1 the WHO2 and, most recently, by the UK Academy of Medical Sciences.3 Estimates of adherence vary widely but are often reported to be as low as 50%.4 When a patient does not take their prescribed medicines as intended, they may not derive the expected outcomes. As well as implications for the individual patient, this can result in increased costs associated with patient hospitalisations or avoidable escalation in other costs of care.3 It may also result in unused medicines, the cost of which is estimated at £300 million per year in England alone.3

Causes of non-adherence are multifactorial. Patients have a right to take or not take medicines and may have logical reasons for their behaviour, for example, fear of, or avoidance of, side effects. Many patients do not take opioid analgesics as frequently as prescribed because of worries about addiction; others may not take a diuretic in the morning if they are going out all day, others may not take a medicine because they perceive it to be ineffective. Non-adherence due to such reasons is known as intentional non-adherence. Other causes of non-adherence are unintentional such as forgetting, challenges in swallowing or simply just having difficulties taking a medicine out of a blister pack. However, whether the reasons for non-adherence are intentional or unintentional, there is a responsibility on the part of the healthcare team to empower the patient to discuss these and, in partnership with the patient, come to an agreed plan to address the patient's goals.

A Cochrane review5 of interventions to enhance adherence suggests there is no single solution, and only a minority of identified studies improved both adherence and clinical outcomes. …