From the Guidelines
The recommended dose of mirabegron for overactive bladder is 25 mg once daily, which can be increased to 50 mg once daily based on individual patient response and tolerability. This recommendation is based on the most recent and highest quality study available, which evaluated the efficacy and safety of mirabegron in patients with overactive bladder 1. The study found that mirabegron 25 mg and 50 mg were effective in reducing symptoms of overactive bladder, with the 50 mg dose providing additional benefits in some patients.
When initiating treatment with mirabegron, it is recommended to start with the 25 mg dose and adjust as needed after 4-8 weeks. Mirabegron can be taken with or without food, and it is essential to administer the medication with water. For patients with severe renal impairment (eGFR 15-29 mL/min/1.73 m²) or moderate hepatic impairment (Child-Pugh Class B), the maximum recommended dose is 25 mg once daily.
The medication works by activating beta-3 adrenergic receptors in the detrusor muscle of the bladder, which improves bladder storage capacity by relaxing the bladder muscle during the filling phase. This mechanism differs from antimuscarinic medications and may result in fewer dry mouth side effects. Common side effects of mirabegron include hypertension, nasopharyngitis, urinary tract infection, and headache. Blood pressure should be monitored regularly, especially in hypertensive patients, as mirabegron can cause blood pressure elevation.
Key points to consider when prescribing mirabegron include:
- Starting dose: 25 mg once daily
- Maximum dose: 50 mg once daily
- Renal impairment: maximum dose 25 mg once daily for severe impairment
- Hepatic impairment: maximum dose 25 mg once daily for moderate impairment
- Administration: with water, with or without food
- Monitoring: regular blood pressure checks, especially in hypertensive patients.
From the FDA Drug Label
The recommended starting dosage of mirabegron extended-release tablets is 25 mg orally once daily. If needed, increase to the maximum dosage of mirabegron extended-release tablets 50 mg orally once daily after 4 to 8 weeks. The recommended dose of mirabegron for overactive bladder is:
From the Research
Mirabegron Dose for Overactive Bladder
The recommended dose of mirabegron for overactive bladder (OAB) has been studied in several clinical trials.
- The studies have investigated the efficacy and safety of mirabegron at daily doses of 25,50, and 100 mg 3, 4, 5.
- Mirabegron at doses of 50 and 100 mg has demonstrated significant improvements in OAB symptoms, including micturition frequency, urgency incontinence, and urgency, as early as the first assessment (week 4) and maintained throughout treatment 3.
- The 25 mg dose has also shown efficacy in improving OAB symptoms, with a good safety profile and high persistence in daily urological practice 6.
- A post-marketing, open-label study in Japan found that add-on therapy with mirabegron 25 mg once daily, with an optional dose increase to 50 mg at week 8, was well tolerated and provided significant improvements in OAB symptoms in patients treated with solifenacin 7.
Key Findings
- Mirabegron 50 and 100 mg demonstrated significant efficacy in treating OAB symptoms, with significant improvements in micturition frequency, urgency incontinence, and urgency 3, 5.
- The 25 mg dose of mirabegron has been found to be effective in improving OAB symptoms, with a good safety profile and high persistence in daily urological practice 6.
- Add-on therapy with mirabegron and an antimuscarinic agent, such as solifenacin, may provide an attractive therapeutic option for patients with OAB 7.
- The most common adverse events observed with mirabegron were hypertension, nasopharyngitis, and urinary tract infection, with a low incidence of dry mouth compared to antimuscarinic agents 3, 4, 5.