Betmira ER 50 | 1 Strip

✔️ Side Effects

The most frequently reported side effects during clinical trials (12-week, double-blind, placebo-controlled) were:

Tachycardia – 1.2%

Urinary tract infection (UTI) – 2.9%

Tachycardia led to treatment discontinuation in 0.1% of patients, while UTIs rarely required discontinuation.
Serious but uncommon effects include atrial fibrillation (0.2%).

✔️ Drug Interactions

With enzyme inhibitors:

Co-administration with strong CYP3A/P-gp inhibitors (e.g., ketoconazole, itraconazole, ritonavir, clarithromycin) increases Mirabegron exposure (AUC ↑1.8-fold).

In patients with mild to moderate renal or hepatic impairment receiving such inhibitors, the dose should be limited to 25 mg once daily.

Not recommended in those with severe renal or moderate hepatic impairment taking strong CYP3A inhibitors.

With enzyme inducers:

CYP3A or P-gp inducers (e.g., rifampicin) may reduce Mirabegron levels, though no dose adjustment is typically required.

With CYP2D6 substrates:

Mirabegron moderately inhibits CYP2D6, increasing plasma concentrations of drugs such as metoprolol (Cmax ↑90%) and desipramine (Cmax ↑79%).

Caution is advised with drugs having a narrow therapeutic index metabolized by CYP2D6 (e.g., thioridazine, tricyclic antidepressants, antiarrhythmics).

With P-gp substrates:

Mirabegron weakly inhibits P-gp, slightly increasing digoxin levels (Cmax ↑29%).

Start digoxin at the lowest possible dose and monitor serum levels.

Other interactions:
No clinically relevant interactions were noted with solifenacin, tamsulosin, warfarin, metformin, or oral contraceptives (ethinylestradiol + levonorgestrel).
No dose adjustment is required.

✔️ Betmira ER is contraindicated in patients with:

Hypersensitivity to Mirabegron or any excipients.

Severe uncontrolled hypertension, defined as systolic BP ≥180 mmHg or diastolic BP ≥110 mmHg.

✔️ Pregnancy & Lactation

Human data on Mirabegron use during pregnancy are limited. Animal studies suggest reproductive toxicity; hence, it is not recommended during pregnancy or for women planning to conceive.

Mirabegron has been detected in animal milk and is presumed to be excreted in human milk. Therefore, breastfeeding is not advised during treatment.

No adverse effects on fertility were observed in animal studies, though the effect on human fertility is unknown.

✔️ Precautions & Warnings

• Renal Impairment: Not recommended for end-stage renal disease or severe impairment with concurrent CYP3A inhibitor use. Dose reduction to 25 mg is advised for severe cases.
• Hepatic Impairment: Avoid in severe hepatic impairment; use caution in moderate cases with strong CYP3A inhibitors.
• Hypertension: May elevate blood pressure; monitor regularly, especially in hypertensive patients.
• QT Prolongation: Use cautiously in patients with congenital or acquired QT prolongation.
• Bladder Outlet Obstruction (BOO): Though clinical studies show no increased urinary retention, use with caution in patients with BOO or those concurrently using antimuscarinic agents for OAB.

✔️ Storage:

Store below 30°C, in a cool, dry place, away from light and moisture.
Keep out of reach of children.