Mirabegron Stada (Mirabegron)

Mirabegron is indicated for conditions affecting bladder storage function within the overactive bladder disease family.

• Overactive bladder: reduces episodes of urgency and incontinence while increasing bladder capacity.
• Urinary frequency: decreases the number of daily voids and improves quality of life.
• Urgency: lessens the sudden, compelling need to void, helping patients regain control.

• Mirabegron activates β3‑adrenergic receptors located in the detrusor smooth muscle of the bladder. This activation stimulates cyclic AMP production, leading to relaxation of the detrusor muscle during the storage phase, thereby increasing functional bladder capacity and reducing involuntary contractions.

Adverse reactions may occur with mirabegron therapy.

Common Side Effects

• Dry mouth: mild to moderate dryness of the oral cavity.
• Constipation: reduced bowel movement frequency.
• Hypertension: increase in blood pressure readings.
• Headache: transient head pain.
• Nasopharyngitis: upper respiratory tract infection symptoms.
• Urinary retention: difficulty initiating or completing voiding.

Serious or Rare Side Effects

• Severe hypertension: markedly elevated blood pressure requiring medical intervention.
• Acute urinary retention: sudden inability to urinate, potentially leading to bladder over‑distension.
• Angle‑closure glaucoma: rapid increase in intra‑ocular pressure.
• Allergic reactions: rash, pruritus, or anaphylaxis.
• Tachycardia: notable increase in heart rate.
• Myocardial infarction: rare occurrence of heart attack.

Before initiating mirabegron, several safety considerations should be observed.

• Blood pressure monitoring: check baseline and periodic readings.
• Urinary retention assessment: evaluate for pre‑existing retention risk.
• Cardiovascular status review: consider underlying heart disease.
• Renal function evaluation: adjust use in severe impairment.
• Avoid use in uncontrolled hypertension: contraindicated in markedly elevated blood pressure.
• Store at below 25°C: keep in the original packaging, protect from moisture and direct sunlight.

Mirabegron may interact with other medicines, requiring attention to avoid altered exposure or additive effects.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole): can markedly increase mirabegron levels.
• Strong CYP2D6 inhibitors (e.g., paroxetine): may raise systemic exposure.
• Concurrent use with other β3‑adrenergic agonists: risk of excessive bladder relaxation.

Moderate Interactions (Monitor Closely)

• Moderate CYP3A4 inhibitors (e.g., erythromycin): may modestly raise concentrations.
• Moderate CYP2D6 inhibitors (e.g., fluoxetine): requires observation.
• Diuretics: combined effect on blood pressure.
• Antihypertensive agents: potential additive hypotensive effect.
• NSAIDs: may enhance risk of hypertension.