Mirabegron


  Issues for Surgery


Risk of increased urinary frequency, urgency and urge incontinence if omitted.


  Advice in the Perioperative period


Elective and Emergency Surgery

Continue.

Post-operative Advice

Monitor renal function – dose reduction may be necessary if renal function is impaired (consult current product literature).

Patients undergoing Overactive Bladder Surgery
Review the need for mirabegron post-operatively.


  Interaction(s) with Common Anaesthetic Agents


None1, 2, 3.


  Interaction(s) with other Common Medicines used in the Perioperative Period


Tramadol

Mirabegron is predicted to increase the exposure to tramadol, but to reduce the exposure to its active metabolite; tramadol adverse effects are therefore increased but not its analgesic effectThe clinical importance of this interaction is unknown. If both drugs are given, be aware of reduced tramadol efficacy and monitor patients for serotonin syndrome (such as fever, tremors, diarrhoea, agitation); concurrent use should be stopped if serotonin syndrome occurs3.

Clarithromycin

Clarithromycin is predicted to increase the exposure to mirabegron – limit the mirabegron dose to 25mg daily with mild to moderate renal impairment or mild hepatic impairment1, 2, 3. Concurrent use is not recommended in severe renal impairment or moderate hepatic impairment2, 3.

QT-Interval Prolongation

Mirabegron has not demonstrated clinically relevant QT-interval prolongation in clinical studies. However, since patient who are taking medicinal products known to prolong the QT-interval were not included in these studies, the manufacturer advises caution when administering mirabegron concurrently with drugs that prolong the QT-interval (e.g. domperidone, clarithromycin, ondansetron)2.


  Further Information


None relevant.


  References


  1. Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 28th June 2019]
  2. Summary of Product Characteristics – Betmiga® (mirabegron) 50mg prolonged-release tablets. Zentiva. Accessed via www.medicines.org.uk 28/06/2019 [date of revision of the text April 2019]
  3. Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 28th June 2019]