Defining and understanding medication adherence

Defining medication adherence

Medication adherence can be defined as the extent to which a person’s behaviour corresponds with taking a medicine optimally. It is key to achieving therapeutic goals and improving patient outcomes. Non-adherence leads to reduced clinical benefit and generates significant waste.  

Non-adherence

Non-adherence is further classified as: 

• Intentional – where the patient decides not to follow the treatment recommendations based on their beliefs and preferences. 
• Unintentional – where the patient wants to follow the treatment recommendations but faces practical barriers, for example poor recall or forgetting to take medication regularly. 

Reasons for behaviours which drive low rates of medication adherence are complex and multifaceted. To impact significantly on medication adherence rates, patients need to be informed, motivated, and skilled (or supported) to take their medicines optimally. Patients may have different views from healthcare professionals about the balance of risks, benefits and side effects of medicines.

Person-centred approach

Interventions with several components, tailored to the needs of individuals in their current social context often lead to more successful outcomes.

Medicines adherence guidance from the National Institute for Health and Care Excellence (NICE) advises no single intervention can solve non-adherence. It proposes that a range of interventions, tailored to each individual, be made available to promote medication adherence.

No single adherence intervention consistently works better than others. Adherence interventions appear most effective when combined with active support from healthcare professionals, rather than simply providing a device or reminder tool.

When tailoring interventions to suit an individual, consider:

• patient circumstances
• medical conditions
• health literacy
• social factors
• behavioural barriers

Asking questions to identify barriers

It is vital to have effective person-centred consultations to find out whether a patient is genuinely taking their medicines or not and gain further insight into this.

The Centre for Pharmacy Postgraduate Education (CPPE) learning programme on consultation skills for pharmacy practice: taking a patient-centred approach offers general training on this.

Reasons for non-adherence can be due to barriers with capability, opportunity or motivation. The following example questions can help with understanding these barriers.

Capability

• How easily can you read these labels?
• How easily can you get your medicines out of this pack or blister?
• How do you manage with using that inhaler – can you show me?
• How many times in the last week did you forget to take a medicine?

Opportunity

• What problems do you have getting your medicines on time?
• Does anyone help you with your medicines?

Motivation

• How do you feel about taking your medicine?
• Can you tell me more about your worries?
• What do you know about why you’ve been given the new medicine?
• What matters most to you about your health?
• How do you think medicines help?

Different adherence barriers require different solutions. Our articles in this series consider common adherence barriers and potential solutions.

Adherence support

Adherence support has historically been provided face-to-face but the utilisation of digital interventions has shown it does not always need to be. Digital tools are most effective when linked to healthcare professional support. Examples include:

• Digital self-management platforms
• Telepharmacy and telepharmaceutical services – more information is available in our article Reminding to take medicines: supporting adherence (SPS page)
• Pharmacist-led mobile health interventions, utilising clinic-like environments alongside digital resources such as mobile applications, text messaging, digital monitoring and app-based adherence support
• Artificial intelligence-enabled communication – this is an upcoming field, but more evidence is required

National and professional guidance

NICE guidance on medicines adherence makes recommendations on how to support and involve people in making an informed choice about their medicines.

The Royal College of Pharmacy resource on Medication review and adherence provides practical guidance to optimise medicines, improve adherence and reduce polypharmacy across all pharmacy settings.

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