Abstract Introduction Following an acute myocardial infarction (AMI), patients are prescribed a daily regime of five medications to prevent secondary cardiovascular events, however medication adherence in this patient group has been measured at only 66%.1 Sub-optimal adherence leads to increased mortality, morbidity and healthcare system costs. Current interventions such as monitored dosage systems, phone message reminders and pharmacist consultations have made some improvements but are largely based on presumptions about adherence than formal evidence. Studying the experience of medication-taking following an AMI, and the personal requirement and adjustment that is required to enable adherence could arguably generate the evidence needed to support future interventions in this field. Aim The aim of this study was to use grounded theory methodology to create a model explaining the process of medication-taking in patients prescribed medication following an AMI. Methods Following ethical approval (UREC 18/36), semi-structured interviews were conducted with thirteen people (based in South-East England) taking medication following at least one AMI episode in the past. The interviews were conducted in person, online or via the telephone and audio-recorded. These recordings were transcribed verbatim and analysed according to constructed grounded theory.2 NVivo software was used to organise and display the coded data and produce a model of the medication-taking process. Results Patients took medication because they wanted to continue living their lives. They saw medication as offering them protection, alongside diet and exercise. Following hospital discharge, patients incorporated medication into their daily routines at home. They used mealtimes and bedtime as a prompt, and kept medication located close to these activities. Patients described rarely missing doses but recognised being away from routines was a cause of medication omission. In this stable stage, patients considered medication-taking unproblematic; they ‘just got on with it’. The professional trust established with the medical team was the basis for following medication directions, and patients conferred the authority to make decisions about their treatment, not wanting to initiate changes themselves; to not ‘rock the boat’. The main cause of change to medication-taking was experiencing adverse bodily effects, ascribed by patients to medication and described as side effects. Patients used small noticeable bodily changes as a prompt for further investigation and information- seeking, after which they presented evidence to the medical team, who instigated medication changes. There was a background dislike of taking medication, which was eased by knowledge of medication action and personal biomedical results. These patients were intentionally adherent to medication but were drawn to question their treatment when ‘side effects’ or misunderstanding arose. Discussion/Conclusion Medication-taking in this group is driven by a desire to live, so they accommodate medication routine to fit their lives, but ‘side effects’ can disturb their intention to continue the routine. This action is reinforced by trust relationships with medical professionals. Resistance to taking medication is alleviated by knowledge of medication action and biomedical results. Practitioners can use patient education, test results and shared decision-making as points to further the patient relationship and strengthen adherence behaviours.