Beetablocker

Beetablocker is not a standard term in medical pharmacology. It is likely a misspelling or informal variant of beta blocker, short for beta-adrenergic blockers, a class of drugs that antagonize beta-adrenergic receptors to blunt sympathetic nervous system effects.

Mechanism of action: By blocking beta-1 and sometimes beta-2 receptors, beetablockers decrease heart rate, reduce myocardial contractility, and slow atrioventricular conduction. They also suppress renin release, aiding blood pressure control. Cardioselective agents preferentially affect the heart; nonselective drugs affect the lungs and vasculature as well.

Medical uses: They are used to treat hypertension, angina, certain arrhythmias, and heart failure with reduced ejection fraction. They also prevent migraines and are used off-label for performance anxiety and certain tremors.

Examples and types: Cardioselective agents include metoprolol and atenolol; nonselective agents include propranolol and nadolol. Some drugs such as carvedilol and labetalol block alpha receptors in addition to beta receptors, providing additional blood pressure effects.

Adverse effects and cautions: Common side effects are fatigue, bradycardia, and hypotension. Nonselective agents may cause bronchospasm in asthma or COPD and can mask hypoglycemia. Contraindications include significant bradycardia, high-grade AV block, and decompensated heart failure; use with caution in diabetes.

History: Beta blockers were developed in the mid-20th century, with propranolol among the first widely used agents, helping transform cardiovascular therapy and treatment of certain anxiety disorders.