Adherence is important for effective DOAC treatment and patients must understand the need to always take their anticoagulant and be committed to continuing to take it. DOACs have a short half-life, so patients who omit doses intentionally or unintentionally are at risk of thrombosis through inadequate anticoagulation. Given that the anticoagulant effects of DOACs fade rapidly on cessation, it is imperative that poor adherence is identified at any patient contact opportunities.

One study established that 30 per cent of patients prescribed dabigatran discontinued treatment in consultation with their doctor at some time between three and 12 months after initiation. When interviewed, patients cited the following reasons for discontinuation:

• Gastrointestinal (GI) symptoms, which led to discontinuation within days of the first dose
• Concerns that there was no antidote available
• Worsening renal function
• Myocardial infarction
• Itching
• Major haemorrhage.

Not all patients who experienced GI symptoms discontinued treatment. Some used a proton pump inhibitor and the alleviation of GI symptoms allowed them to persist with dabigatran. These issues could be discussed during an NMS or MUR.