Background On September 7^th 2015, the European Medicines Agency (EMA) and the Spanish Agency for Medicines and Health Products (AEMPS) notified a drug safety warning (DSW) through a communication to healthcare professionals on the use of mirabegron. It showed new recommendations for its use in relation to the risk of increased blood pressure.

Purpose To detect patients under mirabegron treatment with an increased risk of hypertension. To make a notification to physicians.

Material and methods Retrospective study involving patients who were prescribed mirabegron from February–July 2015 in a health area of 450.000 inhabitants. The following data were obtained by querying the electronic prescription billing system (Microstrategy): sanitary identification number (NUHSA) of patients under mirabegron treatment, prescribers and their medical service. Furthermore, we obtained the NUHSA of patients under main therapeutic groups of antihypertensive drugs (AD) treatment: angiotensin converting enzyme inhibitors, angiotensin II-receptor antagonists and calcium antagonists. Patients under mirabegron treatment and any AD were both identified. These patients were defined as patients with increased risk of hypertension during treatment with mirabegron. We did a report that included: a summary of the DSW, an analysis of the prescribing physicians and patients with increased risk of adverse reaction (AR). This report was sent to all physicians.

Results After analysing 6 months, 810 patients were treated with mirabegron. 41.5% of them (N=336) belonged to the Urology service, while the other prescriptions were evenly distributed among other services. The Urology service was considered urgent to send the report. From all the patients under mirabegron treatment, 45% (N=365) had been treated with any AD, implying a higher risk for the AR or possibility of having already had it. A report was sent by pharmacist to show data of patients under both drugs treatment and physicians prescribing mirabegron. It will help to revise the prescriptions when necessary. The report included information about other treatment options.

Conclusion Five out of ten patients under mirabegron treatment can be considered as risk population for hypertension. The analysis allows prioritisation on the diffusion of information identifying patients at risk and main prescribers. Further studies would be necessary to confirm the impact of this intervention.

References and/or Acknowledgements

1. http://www.aemps.gob.es/https://sinaem.agemed.es/CartasFarmacovigilanciaDoc/2015/DH

2. CP-Betmiga-07-septiembre-2015.pdf. Consulted: 8/09/2015.

References and/or AcknowledgementsNo conflict of interest.