Metoprololsuccinat Orion (Metoprolol Tartrate)

Metoprolol is indicated for several cardiovascular conditions that involve excessive sympathetic stimulation.

• Hypertension: lowers systemic blood pressure and reduces cardiovascular risk in patients with elevated arterial pressure.
• Angina pectoris: decreases myocardial oxygen demand, relieving chest pain during exertion.
• Post‑myocardial infarction: improves survival by reducing the workload on the heart after an infarct.
• Chronic heart failure: enhances ventricular function and decreases hospitalisation rates.
• Cardiac arrhythmias: controls heart rate in supraventricular tachyarrhythmias and atrial fibrillation.

• Metoprolol selectively blocks β1‑adrenergic receptors in cardiac tissue, diminishing the effects of endogenous catecholamines. This antagonism reduces heart rate, myocardial contractility, and cardiac output, leading to lower arterial pressure and decreased myocardial oxygen consumption, which underpins its antihypertensive, anti‑anginal, antiarrhythmic, and heart‑failure benefits.

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

Common Side Effects

• Fatigue or tiredness
• Dizziness or light‑headedness
• Headache
• Bradycardia (slow heart rate)
• Cold extremities
• Gastrointestinal upset (nausea, abdominal discomfort)

Serious or Rare Side Effects

• Severe bradycardia or heart block
• Marked hypotension
• Bronchospasm, especially in patients with asthma or COPD
• Allergic reactions (rash, angioedema)
• Depression or mood changes
• Worsening of heart failure symptoms

Before initiating therapy, clinicians should evaluate patient‑specific factors and monitor for potential complications.

• Cardiovascular assessment: verify baseline heart rate and blood pressure.
• Respiratory conditions: use cautiously in asthma or chronic obstructive pulmonary disease.
• Diabetes monitoring: monitor blood glucose as β‑blockade may mask hypoglycaemia signs.
• Concomitant beta‑blockers: avoid duplicate therapy to prevent excessive bradycardia.
• Renal or hepatic impairment: dose adjustment may be required.
• Pregnancy considerations: safety not established; weigh benefits against potential risks.
• Store at ambient temperature: keep in the original pack, protect from moisture.

Metoprolol can interact with several drug classes, influencing its efficacy and safety profile.

Major Interactions (Avoid)

• Non‑selective beta‑blockers: additive bradycardia and hypotension.
• Calcium‑channel blockers (verapamil, diltiazem): may cause severe conduction delays.
• Class IA/III anti‑arrhythmics (e.g., quinidine, amiodarone): increase risk of heart block.
• Clonidine abrupt withdrawal: precipitates rebound hypertension.
• Insulin or oral hypoglycaemic agents: may enhance hypoglycaemic effects.

Moderate Interactions (Monitor Closely)

• ACE inhibitors or ARBs: potential for additive blood‑pressure lowering.
• Diuretics: may exacerbate electrolyte disturbances.
• NSAIDs: can reduce antihypertensive efficacy.
• SSRIs or other antidepressants: monitor for bradycardia.
• Antithyroid drugs: may affect heart rate control.