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<div> Due to the high prevalence and great cardiovascular risks of hypertension, we need effective and evidence-based treatment strategies. Health-promoting one-way text messages could be a beneficial complement to antihypertensive drugs. However, this has yet to be proven in a primary healthcare setting. The purpose of this study was to investigate if health-promoting text messages could improve patients’ blood pressure in primary care. The PUSHME (Primary care Usage of Health promoting Messages) randomized controlled trial included 401 patients from 10 primary health care centers in southern Sweden. Patients in the intervention group received four text messages weekly for six months along with treatment as usual. The PUSHME study was registered on clinicaltrials.gov (NCT04407962). Patients in both the control group and the intervention group lowered their blood pressure during the study, but there was no significant difference in change between the groups. However, subgroup analyses showed that there was a significantly larger reduction in diastolic blood pressure favoring the intervention for patients with poor self-rated health: -4.5 mmHg vs -1.4 mmHg (p = 0.019), and patients with a sedentary lifestyle: -5.2 mmHg vs -2.4 mmHg (p = 0.034). Our findings indicate that text messages with lifestyle advice to a general hypertensive population do not have any significant effect on blood pressure. However, it could be an effective complement to conventional antihypertensive drug treatment for specific patient groups. </div>