Atenolol (Tenormin)

Pharmacologic profile and clinical uses

Description/Definition

Atenolol is a cardioselective beta-1 adrenergic blocker used primarily in the treatment of hypertension and angina pectoris. It is also used for secondary prevention post-myocardial infarction.

Mechanism of action

Atenolol selectively inhibits beta-1 adrenergic receptors primarily located in cardiac tissue, leading to decreased heart rate, myocardial contractility, and cardiac output, thus reducing blood pressure.

Indications

Hypertension; Angina pectoris; Acute myocardial infarction as part of secondary prevention; Arrhythmias such as supraventricular tachycardia.

Key aspects of drug therapy management

Dosage and administration

• Hypertension: Typically 50 mg once daily, can be increased to 100 mg if needed.
• Angina: 50-100 mg once daily
• Myocardial Infarction: Initial IV administration followed by 50 mg orally every 12 hours.
• Adjust dosage for renal impairment as atenolol is renally excreted.

Side effects

Bradycardia; Hypotension; Fatigue and dizziness; Cold extremities; Potential exacerbation of asthma/COPD due to loss of cardioselectivity at higher doses.

Drug interactions

• Concurrent use with other antihypertensives may potentiate hypotensive effects.
• May mask symptoms of hypoglycemia in diabetic patients.
• Non-dihydropyridine calcium channel blockers (e.g., verapamil, diltiazem) can increase risk of bradycardia and heart block.

Contraindications

• Sinus bradycardia and Heart block greater than first degree.
• Cardiogenic shock.
• Prognosis/Considerations..
• Atenolol is generally well-tolerated and effective in reducing blood pressure and anginal symptoms. However, it should be used cautiously in patients with respiratory conditions and diabetes.

Monitoring

• Blood pressure and heart rate should be regularly monitored.
• Renal function in patients with renal impairment.