From the Guidelines
If Myrbetriq (mirabegron) 50mg daily isn't controlling your urinary frequency and urgency symptoms, you should consider combination therapy with an anticholinergic, such as solifenacin, as the most effective alternative, as evidenced by the BESIDE trial 1. This approach has been shown to be superior to mirabegron monotherapy in reducing urinary incontinence episodes and micturitions per 24 hours. Before making any medication changes, it's essential to ensure you're practicing bladder training techniques, limiting caffeine and alcohol intake, and maintaining proper fluid intake. You should also be evaluated to rule out urinary tract infection or other conditions that might cause similar symptoms. Myrbetriq works by relaxing the bladder muscle through beta-3 adrenergic receptor stimulation, while anticholinergics block acetylcholine receptors that trigger bladder contractions, explaining why combining these approaches can be particularly effective for difficult cases. Some key points to consider:
- Combination therapy with solifenacin and mirabegron has been shown to be effective in reducing urinary incontinence episodes and micturitions per 24 hours 1.
- Anticholinergics, such as oxybutynin, solifenacin, or tolterodine, can be used as an alternative or in combination with mirabegron for resistant symptoms.
- Increasing the dose of mirabegron to 75mg daily may also be considered, but the evidence for this approach is less strong compared to combination therapy 1.
- Any medication changes should be made under medical supervision due to potential side effects, such as dry mouth, constipation, and dyspepsia, which are commonly associated with anticholinergics 1.
From the FDA Drug Label
2.2 Recommended Dosage for Adult Patients with OAB Mirabegron Monotherapy 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 patient is already taking the maximum recommended dose of 50mg daily. Since the patient is experiencing continuation of frequency and urgency, and the dose is already at the maximum recommended level, there is no room for dose increase. Alternative treatments should be considered. 2
From the Research
Alternative Treatment Options
If Mybetriq 50mg daily is not effective in managing overactive bladder symptoms, such as frequency and urgency in females, alternative treatment options can be considered.
- Mirabegron, a β-3 agonist, has been shown to be effective in reducing symptoms of overactive bladder, including incontinence, urgency, and frequency, with a good safety profile 3, 4.
- Antimuscarinic agents, such as oxybutynin, tolterodine, trospium chloride, darifenacin, and solifenacin, can also be used to treat overactive bladder symptoms, but may have a higher risk of anticholinergic side effects, such as dry mouth, constipation, and cognitive impairment 5, 6.
Dose Increase
Regarding increasing the dose of Mybetriq, studies have shown that mirabegron 100mg can be effective in reducing symptoms of overactive bladder, but may have a slightly increased risk of hypertension and cardiac arrhythmia compared to the 50mg dose 4.
- However, the decision to increase the dose should be made under the guidance of a healthcare professional, taking into account the individual patient's response to treatment and potential side effects.
Comparison of Treatment Options
Comparative studies have shown that mirabegron has a similar efficacy to antimuscarinic agents, such as solifenacin and tolterodine, but with a better safety profile and fewer anticholinergic side effects 3, 4.
- Additionally, combination therapy with mirabegron and an antimuscarinic agent, such as solifenacin, may provide an efficacy benefit compared to mirabegron alone, but with a higher risk of anticholinergic side effects 3.