mirabegron: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
mirabegron: clinical details
Prescribing considerations
- Confirm the indication and assess blood pressure before starting.
- Review renal and hepatic function because impairment increases exposure and may restrict use, especially with strong CYP3A inhibitors.
- Assess bladder outlet obstruction, incomplete emptying and concurrent antimuscarinic treatment because urinary retention has been reported.
- Use caution with congenital or acquired QT prolongation or medicines that prolong the QT interval.
- For paediatric neurogenic detrusor overactivity, formulation selection is weight-based and treatment requires periodic reassessment.
Contraindications and cautions
- Hypersensitivity to mirabegron or an excipient.
- Severe uncontrolled hypertension, defined by the selected SmPC as systolic blood pressure at least 180 mmHg and/or diastolic blood pressure at least 110 mmHg.
Monitoring
- Measure blood pressure at baseline and periodically, particularly in people with hypertension.
- Monitor for urinary retention with bladder outlet obstruction or concurrent antimuscarinic treatment.
- Review pulse or rhythm if palpitations or tachycardia occur.
- Monitor serum digoxin concentrations when clinically indicated during concurrent treatment.
- Periodically reassess benefit and safety in paediatric neurogenic detrusor overactivity.
Clinical pharmacology
Mirabegron selectively stimulates bladder beta-3 adrenoceptors, increasing cyclic AMP and relaxing detrusor smooth muscle during storage. It is metabolised through several pathways, moderately inhibits CYP2D6 and weakly inhibits P-glycoprotein; its terminal elimination half-life is approximately 50 hours.
Formulation and product differences
- The selected products are prolonged-release tablets and must not be chewed, divided or crushed.
- Adult overactive-bladder tablets may be taken with or without food; paediatric neurogenic-detrusor-overactivity tablets should be taken with food.
- Tablet and oral-suspension exposure differs, so paediatric formulation selection and switching must follow product-specific instructions.
mirabegron preparations and strengths
Modified-release tablet
Route: Oral
Strengths: 25 mg, 50 mg
mirabegron interactions
A medicine review is important because mirabegron can affect the exposure or safety of several medicines.
Digoxin
Mirabegron can increase digoxin exposure; serum digoxin concentrations should guide prescribing when used together.
CYP2D6 substrates with a narrow therapeutic index, including flecainide, propafenone, thioridazine and some tricyclic antidepressants
Mirabegron can inhibit their metabolism and increase exposure, requiring caution and clinical review.
Strong CYP3A/P-glycoprotein inhibitors, including clarithromycin, itraconazole, ketoconazole and ritonavir
These can increase mirabegron exposure; kidney and liver function may affect whether the combination is suitable.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.