Section 17 · Monograph
Mirabegron
Reviewed Nov 2026FDA label
MyrbetriqBeta-3 agonist
- Forms
- ER tab: 25, 50mg | Granules (oral suspension)
- Dose
- Adults: 25mg once daily, increase to 50mg after 4-8 weeks | Pediatric NDO age 3+: weight-based; 35kg or more 25mg daily, up to 50mg after 4-8 weeks, with food
- MOA
- Beta-3 adrenergic agonism, relaxes detrusor during filling
Indications
- Overactive bladder in adults (monotherapy or with solifenacin)FDA-labeled
- Neurogenic detrusor overactivity in pediatric patients 3 years and olderFDA-labeled
Mechanism of Action
- Beta-3 adrenergic receptor agonist that relaxes the detrusor during bladder filling, increasing capacity
Full Dosing
Adult / usual
- Swallow tablets whole; do not chew, divide or crush
Renal
- Adults: 25mg once daily; may increase to 50mg after 4-8 weeks; maximum 25mg/day in severe renal impairment (eGFR 15-29) or moderate hepatic impairment
Pediatric
- Pediatric NDO age 3+: weight-based; patients 35kg or more may use extended-release tablets 25mg once daily with food, increasing to 50mg after 4-8 weeks; patients under 35kg use granules (not substitutable mg-for-mg)
Contraindications
- None listed in labeling
Drug Interactions
- Moderate CYP2D6 inhibition raises metoprolol and desipramine levels
- Digoxin levels increase — use the lowest digoxin dose
- May be combined with solifenacin per label
Adverse Effects
- Increase in blood pressure (hypertension)
- Urinary tract infection, nasopharyngitis, headache
- Angioedema
- Urinary retention in bladder outlet obstruction
Monitoring Parameters
- Blood pressure periodically
- Post-void residual in neurogenic bladder
Pregnancy & Lactation
- Limited data; use only if benefit justifies risk
- Excreted in milk in animals