Mirabegron Teva (Mirabegron)

Mirabegron is a β3‑adrenergic receptor agonist used to treat conditions within the overactive bladder disease family.

• Overactive bladder: improves bladder capacity and reduces urgency episodes.
• Urinary urgency: decreases frequency of sudden urges to void.
• Urinary frequency: lowers daytime voiding episodes.
• Urge urinary incontinence: reduces episodes of involuntary leakage.

• Mirabegron selectively stimulates β3‑adrenergic receptors located in the detrusor smooth muscle of the urinary bladder. Activation of these receptors leads to relaxation of the detrusor muscle, increasing bladder storage capacity and reducing involuntary contractions that cause urgency, frequency, and urge incontinence.

Mirabegron may cause a range of adverse reactions, which are categorized by frequency and severity.

Common Side Effects

• Hypertension: elevated blood pressure observed in some patients.
• Nasopharyngitis: mild upper respiratory tract infection symptoms.
• Headache: transient mild to moderate head pain.
• Constipation: reduced bowel motility leading to hard stools.
• Dry mouth: decreased salivary secretion.
• Urinary retention: difficulty initiating or maintaining urine flow.

Serious or Rare Side Effects

• Severe hypertension: marked increase in blood pressure requiring medical intervention.
• Angioedema: swelling of face, lips, tongue or throat that may compromise airway.
• Cardiac arrhythmias: irregular heart rhythms, including tachycardia.

Before initiating therapy, clinicians should consider several safety aspects.

• Monitor blood pressure: check baseline and periodic readings during treatment.
• Assess renal function: adjust use in patients with impaired kidney function.
• Review cardiovascular history: use caution in patients with uncontrolled hypertension or heart disease.
• Avoid use in uncontrolled hypertension: contraindicated when systolic BP exceeds 180 mmHg.
• Use caution in the elderly: increased susceptibility to adverse effects.
• Store at room temperature: keep in the original pack, protect from moisture and direct sunlight.

Mirabegron can interact with other medicines, affecting its efficacy or safety.

Major Interactions (Avoid)

• Strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine): may increase mirabegron plasma levels.
• Antihypertensive agents (e.g., β‑blockers, ACE inhibitors): mirabegron may reduce their blood‑pressure‑lowering effect.

Moderate Interactions (Monitor Closely)

• CYP3A4 inhibitors (e.g., ketoconazole, erythromycin): may modestly raise mirabegron concentrations.
• Diuretics: combined use can affect fluid balance and blood pressure.
• Digoxin: mirabegron may increase digoxin levels, requiring monitoring.