Metoprolol 1 A Pharma (Metoprolol Tartrate Ph. Eur.)

Metoprolol tartrate is a selective β1‑adrenergic antagonist used in several cardiovascular conditions.

• Hypertension: reduces systolic and diastolic pressure by decreasing cardiac output.
• Angina pectoris: lowers myocardial oxygen demand, relieving chest pain.
• Post‑myocardial infarction: improves survival by limiting arrhythmias and remodeling.
• Chronic heart failure: enhances ventricular function and reduces hospitalisation.
• Cardiac arrhythmias: controls ventricular rate in atrial fibrillation and other supraventricular tachyarrhythmias.

• Metoprolol tartrate selectively blocks β1‑adrenergic receptors in cardiac tissue, inhibiting catecholamine‑induced stimulation of adenylate cyclase. This reduces intracellular cyclic AMP, leading to decreased heart rate, contractility, and conduction velocity, which together lower cardiac output and myocardial oxygen consumption, ultimately producing antihypertensive and anti‑ischemic effects.

Metoprolol tartrate may cause a range of adverse reactions, from mild to severe.

Common Side Effects

• Fatigue: feeling unusually tired or weak.
• Dizziness or light‑headedness, especially on standing.
• Cold extremities: reduced peripheral circulation.
• Bradycardia: slower than normal heart rate.
• Gastrointestinal upset: nausea, abdominal discomfort.
• Headache: mild to moderate intensity.

Serious or Rare Side Effects

• Bronchospasm: difficulty breathing, particularly in asthmatic patients.
• Severe bradycardia or heart block requiring medical attention.
• Marked hypotension: sudden drop in blood pressure.
• Allergic reactions: rash, itching, swelling, or anaphylaxis.
• Depression or mood changes.
• Worsening heart failure symptoms.

Before prescribing Metoprolol tartrate, clinicians should consider several safety measures.

• Assess cardiovascular status: evaluate heart rate and blood pressure prior to initiation.
• Monitor for bronchospastic disease: avoid or use with caution in uncontrolled asthma or COPD.
• Adjust in renal impairment: dose may need modification in reduced kidney function.
• Caution in diabetes: beta‑blockade can mask hypoglycaemia symptoms.
• Avoid abrupt discontinuation: taper gradually to prevent rebound tachycardia.
• Store at ambient temperature: keep below 25°C, protect from moisture and light.

Metoprolol tartrate can interact with other medicines, altering its efficacy or safety.

Major Interactions (Avoid)

• Other AV‑nodal blockers (e.g., verapamil, diltiazem): may cause severe bradycardia.
• Potent CYP2D6 inhibitors (e.g., quinidine, propafenone): increase plasma metoprolol levels.
• Insulin or sulfonylureas: beta‑blockade may mask hypoglycaemia signs.

Moderate Interactions (Monitor Closely)

• NSAIDs: may blunt antihypertensive effect.
• SSRIs or other antidepressants: can enhance bradycardia risk.
• Thyroid hormones: may alter heart‑rate response, requiring dose adjustment.