propranololo

Propranolol, including propranololo in some languages, is a nonselective beta-adrenergic receptor blocker (beta-blocker). It blocks both beta-1 and beta-2 receptors, reducing heart rate, myocardial contractility, AV conduction, and renin release, and it is highly lipophilic, enabling substantial tissue distribution and central nervous system penetration.

Because of beta-2 blockade in the airways, propranolol can cause bronchospasm and should be used with caution or avoided in asthma or significant COPD. It may also mask hypoglycemia symptoms in diabetes and can worsen bradycardia or heart failure in susceptible patients.

Uses include hypertension, angina, certain arrhythmias, and the prevention of myocardial infarction. It is also used for migraine prophylaxis and for symptom control in hyperthyroidism and certain anxiety disorders, such as performance anxiety.

Propranolol is available in oral immediate-release and extended-release forms, and intravenously for acute tachyarrhythmias. It is extensively metabolized by the liver, with a half-life that varies by formulation.

Common adverse effects are fatigue, dizziness, bradycardia, hypotension, and bronchospasm. Contraindications include severe bradycardia, AV block without a pacemaker, uncompensated heart failure, cardiogenic shock, and significant airway disease. Caution is advised in diabetes and in patients taking other antihypertensives or insulin, due to masking of hypoglycemia and additive effects.

Propranolol was developed in the 1960s and became the first successful beta-blocker, marketed initially as Inderal. It paved the way for later cardioselective agents.