Mirabegron Glenmark (Mirabegron)

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

• Overactive bladder: reduces urgency and frequency, increasing functional bladder capacity.
• Urinary urgency: lessens the sudden, compelling need to void.
• Urinary frequency: decreases the number of voids during the day.

• Mirabegron selectively activates β3‑adrenergic receptors on detrusor smooth muscle. This activation raises intracellular cyclic AMP, leading to relaxation of the detrusor muscle during the storage phase, thereby expanding bladder capacity and diminishing involuntary contractions that cause urgency and frequency.

Adverse reactions may occur with Mirabegron therapy.

Common Side Effects

• Hypertension: elevated blood pressure observed in some patients.
• Nasopharyngitis: mild upper respiratory tract infection symptoms.
• Headache: intermittent mild to moderate head pain.
• Constipation: reduced bowel motility.
• Dry mouth: decreased salivation.
• Urinary retention: difficulty initiating or completing voiding.

Serious or Rare Side Effects

• Severe hypertension: markedly high blood pressure requiring medical intervention.
• Acute urinary retention: sudden inability to urinate, potentially needing catheterisation.
• Cardiovascular events: chest pain or arrhythmia.
• Angioedema: swelling of face, lips, or throat.
• Allergic reactions: rash, pruritus, or anaphylaxis.
• QT interval prolongation: rare cardiac conduction abnormality.

Before initiating Mirabegron, clinicians should consider several safety measures.

• Blood pressure monitoring: check baseline and periodic readings.
• Urinary retention assessment: evaluate for pre‑existing retention.
• Renal and hepatic function: adjust use if impairment is present.
• Concomitant antihypertensives: review to avoid excessive blood pressure lowering.
• Uncontrolled hypertension: avoid use in patients with markedly elevated pressure.
• Store at ambient temperature: keep in the original pack, protect from moisture.

Mirabegron can affect the pharmacokinetics of several co‑administered drugs.

Major Interactions (Avoid)

• Strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine): may increase Mirabegron exposure.
• Potent CYP3A4 inhibitors (e.g., ketoconazole, itraconazole): can raise plasma levels.
• Other β3‑adrenergic agonists: additive bladder‑relaxant effect.

Moderate Interactions (Monitor Closely)

• CYP2D6 substrates (e.g., metoprolol, tamoxifen): may have altered clearance.
• CYP3A4 substrates (e.g., midazolam, calcium channel blockers): monitor for increased effects.
• Diuretics: concurrent use may heighten risk of hypertension.